JP6609198B2 - Combined heat source heat pump device - Google Patents

Description

  The present invention relates to a combined heat source heat pump apparatus that can supply a circulating fluid that has been subjected to heat exchange with respect to a refrigerant in a heat pump circuit after heat exchange with a heat medium or outdoor air in a heat source connection path to a load terminal, and that can perform air conditioning. .

  Conventionally, in this type of combined heat source heat pump apparatus, as described in Patent Document 1, when using a heat pump circuit that exchanges heat with a heat medium and a heat pump circuit that exchanges heat with outdoor air, the outside air temperature and the reference temperature are By comparison, some compressors of one heat pump circuit are used as a main power source, and the compressor of the other heat pump circuit is switched as an auxiliary power source to control driving.

Japanese Patent Laying-Open No. 2015-117880

  In this conventional system, when the main power source and the auxiliary power source are switched, the driving condition of the compressor that has been driven as the main power source until then, and the driving of the compressor that has been driven as the auxiliary power source until then. However, if the cooling / heating load increases immediately before switching between the main power source / auxiliary power source, there is a large difference between the actual circulating fluid temperature and the target circulating fluid temperature in the load side circuit. When a temperature deviation occurs, and when it is simply reversed as described above, the rotation speed of the compressor starts to be adjusted from that time until the temperature of the circulating fluid in the load side circuit reaches the target circulating fluid temperature. Took a long time and could impair comfort.

In order to solve the above problems, in claim 1 of the present invention, the first compressor, the first load side heat exchanger, and the first heat source side heat exchanger are connected by a first refrigerant pipe, and A first heat source side heat exchanger and a predetermined heat source are connected by a heat medium pipe to form a first heat pump circuit, and a second compressor, a second load side heat exchanger, and a second heat exchanger that can exchange heat with outside air. 2 heat source side heat exchangers are connected by a second refrigerant pipe to form a second heat pump circuit, the first load side heat exchanger, the second load side heat exchanger, at least one load terminal, The first load side heat exchanger is connected in series with a circulating fluid pipe while being arranged in series upstream of the second load side heat exchanger to form a load side circuit. Which one of the first compressor and the second compressor is the main power source and which is the auxiliary power source Obtain, possess and control means, and in the composite source heat pump apparatus which performs heating operation by the load terminal, in the load circuit, circulating fluid temperature detection means for detecting the circulating fluid temperature flowing into the load-side heat exchanger And an outside air temperature detecting means for detecting the outside air temperature, and the control means, during the operation, with the second compressor as a main power source and the first compressor as an auxiliary power source, When the outside air temperature detected by the outside air temperature detecting means becomes lower than a predetermined reference temperature, the first compressor is used as a main power source and the second compressor is used as an auxiliary power source. It was carried out, and the first compressor the circulating fluid temperature by the main power Toshikatsu Minamoto said second compressor immediately before Ru switched to a state with the auxiliary power source and the circulating fluid temperature detecting means detects drops about Thus the circulating fluid temperature and if the deviation between the target circulating fluid temperature exceeds a predetermined threshold value, the compressor rotational speed of the main power source and became the first compressor to the switching and simultaneous The maximum rotation speed is increased.

According to a second aspect of the present invention, the control means is in a case where a state in which it is determined that switching between the compressor as the main power source and the compressor as the auxiliary power source is necessary continues for a predetermined period, and , Immediately before switching to the state where the first compressor is used as a main power source and the second compressor is used as an auxiliary power source, the deviation is caused by a decrease in the circulating fluid temperature detected by the circulating fluid temperature detecting means. if it becomes more than the threshold value, the rotational speed of the main power source and became the first compressor to the switching simultaneously are those which increase the maximum rotational speed of the compressor.

According to a third aspect of the present invention, the load side circuit connects a plurality of the load terminals, the first load side heat exchanger, and the second load side heat exchanger. When the state determined to require switching between the compressor as the power source and the compressor as the auxiliary power source has continued for a predetermined period, and the second compressor is used as the main power source. Immediately before switching to a state in which the compressor is used as an auxiliary power source, the deviation becomes the threshold due to a decrease in the circulating fluid temperature detected by the circulating fluid temperature detecting means due to an increase in the number of load terminals to be operated. when a value or more, the rotation speed of the became switched simultaneously the main power source of the first compressor is intended to increase the maximum rotational speed of the compressor.

In order to solve the above problem, in claim 4 of the present invention , the first compressor, the first load side heat exchanger, and the first heat source side heat exchanger are connected by the first refrigerant pipe. The first heat source side heat exchanger and a predetermined heat source are connected by a heat medium pipe to form a first heat pump circuit, and can exchange heat with the second compressor, the second load side heat exchanger, and outside air. A second heat source side heat exchanger connected by a second refrigerant pipe to form a second heat pump circuit, the first load side heat exchanger, the second load side heat exchanger, and at least one load terminal Are connected with a circulating fluid pipe while the first load side heat exchanger is arranged in series upstream of the second load side heat exchanger to form a load side circuit. Which of the first compressor and the second compressor is the main power source and which is the auxiliary power source In the combined heat source heat pump apparatus that performs cooling operation by the load terminal, the circulating fluid temperature detecting unit that detects the circulating fluid temperature flowing into the load side heat exchanger in the load side circuit And an outside air temperature detecting means for detecting the outside air temperature, and the control means, during the operation, with the second compressor as a main power source and the first compressor as an auxiliary power source, When the outside air temperature detected by the outside air temperature detecting means becomes higher than a predetermined reference temperature, switching to a state where the first compressor is used as a main power source and the second compressor is used as an auxiliary power source. And the circulating fluid temperature detected by the circulating fluid temperature detecting means is increased immediately before switching to a state where the first compressor is used as a main power source and the second compressor is used as an auxiliary power source. Thus, when the deviation between the circulating fluid temperature and the target circulating fluid temperature exceeds a predetermined threshold value, the rotational speed of the first compressor that has become the main power source simultaneously with the switching is determined. The maximum rotation speed is increased .

According to a fifth aspect of the present invention, the control means includes a state in which it is determined that switching between the compressor as the main power source and the compressor as the auxiliary power source is necessary continues for a predetermined period, and Immediately before switching to the state where the first compressor is used as a main power source and the second compressor is used as an auxiliary power source, the deviation is caused by an increase in the circulating fluid temperature detected by the circulating fluid temperature detecting means. When the threshold value is exceeded, the rotational speed of the first compressor that has become the main power source simultaneously with the switching is increased to the maximum rotational speed of the compressor.
According to a sixth aspect of the present invention, the load side circuit connects a plurality of the load terminals, the first load side heat exchanger, and the second load side heat exchanger. When the state determined to require switching between the compressor as the power source and the compressor as the auxiliary power source has continued for a predetermined period, and the second compressor is used as the main power source. Immediately before switching to a state in which the compressor is used as an auxiliary power source, the deviation becomes the threshold due to an increase in the circulating fluid temperature detected by the circulating fluid temperature detecting means due to an increase in the number of load terminals to be operated. When the value exceeds the value, the rotational speed of the first compressor that has become the main power source simultaneously with the switching is increased to the maximum rotational speed of the compressor.

According to claim 1 of the present invention, two heat pump circuits capable of collecting or radiating heat from different heat sources are provided. The first heat pump circuit includes a predetermined heat source, a first heat source side heat exchanger, a first compressor, and a first load side heat exchanger, and the second heat pump circuit includes outside air as a heat source. A second heat source side heat exchanger capable of heat exchange, a second compressor, and a second load side heat exchanger are provided. At this time, the first load-side heat exchanger and the second load-side heat exchanger are connected to a load-side circuit through which the circulating fluid piping circulates, and the upstream side first load-side heat exchanger is connected to the first heat pump circuit side. After the heat exchange with the circulating fluid, the circulating fluid exchanged with the second heat pump circuit side by the second load side heat exchanger on the downstream side is supplied to the load terminal.

  Thus, in the load-side circuit capable of performing both heat exchange in the first load-side heat exchanger and heat exchange in the second load-side heat exchanger, the control means is usually based on the outside air temperature. Switching between heat exchange and main heat exchange. For example, at the time of cooling operation, when the outside air temperature is low, large heat radiation to the outside air can be expected. Therefore, the second compressor is driven as a main power source, and the first compressor is driven as an auxiliary power source. On the other hand, when the outside air temperature is high, the first compressor is driven as a main power source and the second compressor is driven as an auxiliary power source because heat radiation to the outside air cannot be expected so much. Also, for example, during heating operation, if the outside air temperature is high, a large heat absorption from the outside air can be expected, so the second compressor is driven as a main power source and the first compressor is driven as an auxiliary power source. . Conversely, when the outside air temperature is low, the first compressor is driven as a main power source and the second compressor is driven as an auxiliary power source because heat absorption from the outside air cannot be expected so much.

  When the outside air temperature changes and it is considered that it is more efficient to change the assignment of the main power source / auxiliary power source up to that time, the control means controls the first compressor and the second compressor. The assignment is switched, and the compressor that has been the main power source until then is driven as an auxiliary power source, and the compressor that has been the auxiliary power source is driven as the main power source.

  However, when the main power source and the auxiliary power source are switched as described above, the driving conditions of the compressor that has been driven as the main power source and the driving of the compressor that has been driven as the auxiliary power source until then. However, if the cooling / heating load increases immediately before switching between the main power source / auxiliary power source, there is a large difference between the actual circulating fluid temperature and the target circulating fluid temperature in the load side circuit. When a temperature deviation occurs, and when it is simply reversed as described above, the rotation speed of the compressor starts to be adjusted from that time until the temperature of the circulating fluid in the load side circuit reaches the target circulating fluid temperature. Takes a long time and may impair comfort.

Therefore, according to claim 1 or claim 4 , the circulating fluid temperature detecting means is provided to detect the circulating fluid temperature flowing into the load side heat exchanger in the load side circuit. When the deviation between the detected circulating fluid temperature and the target temperature of the circulating fluid by circulating fluid temperature is lowered (or raised) becomes equal to or larger than a predetermined threshold, the load side circuit as it regarded as the temperature of the circulating fluid requires a long time to the target circulating fluid temperature, in order to avoid this, the rotational speed of the first compressor become the main power source to switch simultaneously to the maximum rotational speed Increase.

As a result, the temperature of the circulating fluid in the load-side circuit is set to the target circulating fluid temperature most quickly after the main power source and the auxiliary power source are switched, and the comfort can be reliably prevented from being impaired.

According to claim 2 or claim 5 , the main power source and the auxiliary power supply are actually supported by waiting for a certain period of time for the change state of the outside air temperature that needs to be switched between the main power source and the auxiliary power source. The control means can reliably determine that switching to the power source is necessary.

According to claim 3 or claim 6 , when the main power source and the auxiliary power source are switched, the circulating fluid temperature and When a large deviation occurs with respect to the target circulating fluid temperature, the state can be quickly eliminated and the deviation can be quickly reduced.

1 is an external configuration diagram of main units of a heat pump apparatus according to an embodiment of the present invention. Circuit diagram of the entire heat pump device The figure explaining the action at the time of heating operation The figure explaining the action at the time of cooling operation Functional configuration diagram of underground heat control device and air heat control device during heating operation Functional configuration diagram of underground heat control device and air heat control device during cooling operation The figure explaining the switching between the main power source and the auxiliary power source during the cooling operation, and the switching between the main power source and the auxiliary power source during the heating operation. The figure showing the setting aspect of the reference temperature which switches the main power source / auxiliary power source at the time of air_conditionaing | cooling operation The figure showing the setting mode of the reference temperature which switches the main power source / auxiliary power source at the time of heating operation The figure showing the behavior of the heat pump apparatus when the fluctuation | variation of a heating load does not generate | occur | produce at the time of switching of a main power source / auxiliary power source at the time of heating operation The figure showing an example of the behavior of the heat pump apparatus when the fluctuation | variation of a heating load generate | occur | produces at the time of switching of a main power source / auxiliary power source at the time of heating operation The figure showing the other example of the behavior of the heat pump apparatus when the fluctuation | variation of the heating load generate | occur | produces at the time of switching of a main power source / auxiliary power source at the time of heating operation The figure showing the behavior of the heat pump apparatus when the fluctuation | variation of the cooling load does not generate | occur | produce at the time of switching of a main power source / auxiliary power source at the time of air_conditionaing | cooling operation. The figure showing an example of the behavior of the heat pump apparatus when the fluctuation | variation of the cooling load generate | occur | produces at the time of switching of a main power source / auxiliary power source at the time of cooling operation The figure showing the other example of the behavior of the heat pump apparatus when the fluctuation | variation of the cooling load generate | occur | produces at the time of switching of a main power source / auxiliary power source at the time of air_conditionaing | cooling operation. The flowchart figure showing the control procedure performed at the time of heating operation The flowchart figure showing the control procedure performed at the time of air_conditionaing | cooling operation

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS.

  FIG. 1 shows an external configuration of a main unit of the heat pump apparatus 1 of the present embodiment to which the composite heat source type heat pump apparatus of the present invention is applied. In FIG. 1, the heat pump device 1 of the present embodiment is a load-side circuit that circulates a circulating liquid L (for example, water or antifreeze liquid) through a ground heat heat pump unit 4, an air heat heat pump unit 5, and a heat exchange terminal 36. Terminal circulation circuit 30 and underground heat circulation circuit 20.

  FIG. 2 shows a circuit configuration of the entire heat pump apparatus 1 of the present embodiment. As shown in FIG. 2, the heat pump device 1 is provided in the geothermal heat pump unit 4 and can heat or cool the circulating liquid L on the heat exchange terminal 36 side using a geothermal heat source. Air as a second heat pump circuit provided in the ground heat heat pump circuit 40 as a circuit and the air heat heat pump unit 5 and capable of heating or cooling the circulating liquid L on the heat exchange terminal 36 side using an air heat source. It has a thermal heat pump circuit 50, the terminal circulation circuit 30, and the underground heat circulation circuit 20 as a first heat pump circuit.

  In FIG. 2, the underground heat pump circuit 40 includes a variable capacity first compressor 43, a first heat exchanger 41 as a first load side heat exchanger, a first expansion valve 44, and a first heat source side. A ground heat source heat exchanger 45 as a heat exchanger is connected in an annular shape by a first refrigerant pipe 42. The first refrigerant pipe 42 is provided with a four-way valve 46 for switching the flow direction of the first refrigerant C1 (see FIGS. 3 and 4 described later) in the geothermal heat pump circuit 40.

  The first heat exchanger 41 and the underground heat source heat exchanger 45 are constituted by, for example, plate heat exchangers. In this plate heat exchanger, a plurality of heat transfer plates are stacked, and the circulating fluid L (or heat medium H1; see FIG. 3 and the like to be described later) serving as a heat medium and a refrigerant flow path for circulating the first refrigerant C1. The fluid flow paths to be circulated are alternately formed with each heat transfer plate as a boundary.

  The temperature of the first refrigerant C1 discharged from the first compressor 43 is detected by the first refrigerant discharge temperature sensor 42a. Similarly, of the refrigerant temperature sensors 42c and 42b provided in the first refrigerant pipe 42 from the first heat exchanger 45 to the underground heat source heat exchanger 45 through the first expansion valve 44, the first expansion is performed. The first refrigerant temperature sensor 42b provided in the first refrigerant pipe 42 from the valve 44 to the underground heat source heat exchanger 45 causes the first refrigerant C1 on the low pressure side (during heating operation) or high pressure side (during cooling operation) to The temperature is detected. The detection results of the first refrigerant discharge temperature sensor 42 a and the first refrigerant temperature sensor 42 b are input to the underground heat control device 61.

  The air heat heat pump circuit 50 includes a variable capacity second compressor 53, a second heat exchanger 51 as a second load side heat exchanger, a second expansion valve 54, and a second heat source side heat exchanger. The air heat source heat exchanger 55 is annularly connected by a second refrigerant pipe 52. The second refrigerant pipe 52 is provided with a four-way valve 58 for switching the flow direction of the second refrigerant C2 (see FIGS. 3 and 4 described later) in the air heat heat pump circuit 50.

  As described above, the second heat exchanger 51 is configured by, for example, a plate heat exchanger, and each of the refrigerant flow path through which the second refrigerant C2 flows and the fluid flow path through which the circulating liquid L flows. It is formed alternately with the heat transfer plate as a boundary.

  The temperature of the second refrigerant C2 discharged from the second compressor 53 is detected by the second refrigerant discharge temperature sensor 52a. The temperature of the outside air is detected by an outside air temperature sensor 57 serving as an outside air temperature detecting means. The detection results of the second refrigerant discharge temperature sensor 52 a and the outside air temperature sensor 57 are input to the air heat control device 62. Further, the detection result of the outside air temperature sensor 57 is also input to the underground heat control device 61.

  In addition, as said 1st refrigerant | coolant C1 of the said geothermal heat pump circuit 40, and said 2nd refrigerant | coolant C2 of the said air heat heat pump circuit 50, arbitrary refrigerant | coolants, such as HFC refrigerant | coolants, such as R410A and R32, and a carbon dioxide refrigerant | coolant, for example Can be used.

  The underground heat circulation circuit 20 is configured to circulate through the underground heat circulation pump 22 having a variable rotation speed (number of rotations per unit time), the underground heat source heat exchanger 45, and the underground heat source heat exchanger 45. A ground heat exchanger 23 installed as a heat source for exchanging heat with one refrigerant C1 (in this example, in the ground) is connected in an annular shape by a ground heat pipe 21 serving as a heat medium pipe. An antifreeze liquid to which ethylene glycol, propylene glycol or the like is added is circulated in the underground heat pipe 21 as a heat medium H1 (see FIGS. 3 and 4 described later) by the underground heat circulation pump 22, and the heat An underground cistern 24 for storing the medium H1 and adjusting the pressure of the underground heat circulation circuit 20 is provided. The underground heat exchanger 23 is not limited to being provided in the ground, but is provided in a relatively large capacity water source such as a lake, a reservoir, a river, the sea, a hot spring, a well, and the like. You may make it thermally radiate.

  The terminal circulation circuit 30 exchanges heat (as two in this example) as load terminals such as the first heat exchanger 41, the second heat exchanger 51, and fan coils, floor heating panels, and panel convectors. A terminal 36 is annularly connected in order from the upstream side by a load pipe 31 as a circulating fluid pipe. In this example, two heat exchange terminals 36 are connected to each other in the terminal circulation circuit 30 in parallel with each other via an appropriate header (not shown). The load pipe 31 is provided with a circulating fluid circulating pump 32 that circulates the circulating fluid L in the terminal circulating circuit 30 and a heating systern 35 that stores the circulating fluid L and adjusts the pressure of the terminal circulating circuit 30. Yes. In this example, the circulating fluid circulation pump 32 is configured to rotate at a constant speed (a constant rotational speed). The heat exchange terminal 36 can be switched between operation and stop by a terminal remote controller (not shown). During operation, the circulating fluid L circulates inside the heat exchange terminal 36 while the operation is stopped. The circulating liquid L does not circulate inside the heat exchange terminal 36. In FIG. 2, two heat exchange terminals 36 are provided in parallel, but one or more heat exchange terminals 36 may be provided, and the quantity and specifications are not particularly limited.

  At this time, in the terminal circulation circuit 30, the first heat exchanger 41 and the second heat exchanger 51 are connected in series, and as described above, the circulating fluid that circulates in the terminal circulation circuit 30. The first heat exchanger 41 is disposed upstream of the second heat exchanger 51 with respect to the flow of L. That is, the heat pump device 1 uses the first heat exchanger 41 of the underground heat pump circuit 40 that heats or cools the circulating liquid L on the heat exchange terminal 36 side using an underground heat source, and an air heat source. The second heat exchanger 51 of the air heat heat pump circuit 50 that heats or cools the circulating liquid L on the heat exchange terminal 36 side is a composite heat source heat pump device connected in series to the terminal circulation circuit 30. Is.

  The load pipe 31 is provided with a return fluid temperature sensor 34 as a circulating fluid temperature detecting means for detecting the temperature of the circulating fluid L flowing into the first heat exchanger 41 from the heat exchange terminal 36. The detection result is input to the underground heat control device 61 and the air heat control device 62. In addition, the structure which acquires the detection result of the return liquid temperature sensor 34 via the said underground heat control apparatus 61 may be sufficient as the air heat control apparatus 62 not directly connected to the return liquid temperature sensor 34.

  Here, the heat pump device 1 can selectively function as a heating device that performs a heating operation by switching the four-way valves 46 and 58 or a cooling device that performs a cooling operation. Next, the heating operation and the cooling operation will be described with reference to FIGS. 3 and 4.

  FIG. 3 shows a state during heating operation. Note that various signal lines shown in FIG. 2 are omitted in order to prevent the illustration from being complicated. In the heating operation shown in FIG. 3, in the geothermal heat pump circuit 40, the first refrigerant C <b> 1 discharged from the first compressor 43 is changed to the first by switching the four-way valve 46 as illustrated. After the first heat exchanger 41, the first expansion valve 44, and the underground heat source heat exchanger 45 are circulated in this order, a flow path that returns to the first compressor 43 is formed. Accordingly, the first heat exchanger 41 functioning as a condenser after the gas-state first refrigerant C1 sucked at low temperature and low pressure is compressed by the first compressor 43 to become high temperature and high pressure gas. Then, heat is exchanged with the circulating fluid L flowing through the terminal circulating circuit 30 to release heat to the circulating fluid L and change into a high-pressure liquid while heating. Thus, the first refrigerant C1 that has become liquid is decompressed by the first expansion valve 44 and becomes a low-pressure liquid that easily evaporates. In the underground heat source heat exchanger 45 that functions as an evaporator, Heat exchange is performed with the heat medium H1 flowing through the heat circulation circuit 20 to evaporate and change into a gas, thereby absorbing heat, and returning to the first compressor 43 again as a low-temperature and low-pressure gas.

  On the other hand, in the air heat heat pump circuit 50, the second refrigerant C2 discharged from the second compressor 53 is converted into the second heat exchanger 51 and the second expansion valve by switching the four-way valve 58 as shown in the figure. 54 and the air heat source heat exchanger 55 are circulated in this order, and then a flow path returning to the second compressor 53 is formed. As a result, the second refrigerant C2 in the gas state sucked at a low temperature and a low pressure is compressed by the second compressor 53 to become a high temperature and a high pressure gas, and then functions as a condenser. Then, heat exchange with the circulating fluid L flowing through the terminal circulating circuit 30 is performed to release heat to the circulating fluid L, which changes into a high-pressure liquid while being heated. The second refrigerant C2 that has become liquid in this manner is decompressed by the second expansion valve 54 and becomes a low-pressure liquid that easily evaporates. In the air heat source heat exchanger 55 that functions as an evaporator, the operation of the blower fan 56 is performed. Heat exchanges with the air sent by the air to evaporate and change to gas, thereby absorbing heat and returning to the second compressor 53 again as a low-temperature and low-pressure gas.

  Further, in the underground heat circulation circuit 20, the underground heat is collected from the underground by the underground heat exchanger 23, and the heat medium H <b> 1 having the heat is exchanged by the underground heat circulation pump 22 for the underground heat source heat exchange. Supplied to the vessel 45. In the underground heat source heat exchanger 45 that functions as an evaporator, the first refrigerant C1 that flows through the refrigerant flow path of the underground heat source heat exchanger 45 and the fluid flow path of the underground heat source heat exchanger 45 are provided. Heat exchange is performed with the circulating heat medium H1, and the underground heat collected by the underground heat exchanger 23 is pumped to the first refrigerant C1 side, and the first refrigerant C1 is heated as described above. .

  Further, in the terminal circulation circuit 30, the circulating liquid L that has flowed into the first heat exchanger 41 by the circulating liquid circulation pump 32 is supplied to the first heat exchanger 41 that functions as a condenser in the underground heat circulation circuit 20. In the second heat exchanger 51 functioning as a condenser, after heat exchange with the heat medium H1 and heat exchange with the first refrigerant C1 heated as described above, the air heat source heat exchange Heat is exchanged with the outside air in the vessel 55 and heat is exchanged with the second refrigerant C2 heated as described above, and further heated. The circulating liquid L thus heated is then supplied to the heat exchange terminal 36 to heat the air-conditioned space.

  In addition, in the above, although the state at the time of the heating operation which operated both the underground heat pump unit 4 and the air heat heat pump unit 5 was shown and demonstrated in FIG. 3, it is not restricted to this. That is, a heating operation in which only the geothermal heat pump unit 4 is operated or a heating operation in which only the air heat heat pump unit 5 is operated is possible.

  FIG. 4 shows a state during the cooling operation. Note that various signal lines shown in FIG. 2 are omitted in order to prevent the illustration from being complicated. In the cooling operation shown in FIG. 4, in the geothermal heat pump circuit 40, the four-way valve 46 is switched as shown in the figure, so that the first refrigerant C <b> 1 discharged from the first compressor 43 is After the medium heat source heat exchanger 45, the first expansion valve 44, and the first heat exchanger 41 are circulated in this order, a flow path that returns to the first compressor 43 is formed. Thus, in the underground heat source exchanger 45 functioning as a condenser after the first refrigerant C1 in the gas state sucked at low temperature and low pressure is compressed by the first compressor 43 to become high temperature and high pressure gas. Then, heat exchange is performed with the heat medium H1 flowing through the underground heat circulation circuit 20, and the heat medium H1 is changed into a high-pressure liquid while releasing heat. Thus, the first refrigerant C1 that has become liquid is decompressed by the first expansion valve 44 and becomes a low-pressure liquid that easily evaporates. In the first heat exchanger 41 that functions as an evaporator, the terminal circulation circuit Heat is exchanged with the circulating fluid L flowing through 30 to evaporate and change into a gas to absorb heat and cool the circulating fluid L, and then return to the first compressor 43 again as a low-temperature and low-pressure gas.

  On the other hand, in the air heat heat pump circuit 50, when the four-way valve 58 is switched as shown, the second refrigerant C2 discharged from the second compressor 53 is supplied to the air heat source heat exchanger 55 and the second expansion valve. 54 and the 2nd heat exchanger 51 are distribute | circulated in order, Then, the flow path which returns to the 2nd compressor 53 is formed. Thereby, the second refrigerant C2 in the gas state sucked at a low temperature and a low pressure is compressed by the second compressor 53 to become a high temperature and a high pressure gas, and then the air heat source heat exchanger 55 functioning as a condenser. , The heat exchange with the air sent by the operation of the blower fan 56 is performed to change the liquid into a high-pressure liquid while releasing heat to the outside air. The second refrigerant C2 that has become liquid in this manner is reduced in pressure by the second expansion valve 54, becomes a low-pressure liquid, and easily evaporates. In the second heat exchanger 51 that functions as an evaporator, the terminal circulation circuit Heat is exchanged with the circulating liquid L flowing through 30 to evaporate and change into gas, thereby absorbing the heat and cooling the circulating liquid L, and then returning to the second compressor 53 again as a low-temperature and low-pressure gas.

  In the underground heat circulation circuit 20, the heat medium H <b> 1 is supplied to the underground heat source heat exchanger 45 by the underground heat circulation pump 22. In the underground heat source heat exchanger 45 that functions as a condenser, the first refrigerant C1 that flows through the refrigerant flow path of the underground heat source heat exchanger 45 and the fluid flow path of the underground heat source heat exchanger 45 are provided. After the circulating heat medium H1 faces and exchanges heat, the heat of the first refrigerant C1 at a high temperature is dissipated to the heat medium H1 side and the first refrigerant C1 is cooled, The heat of the medium H1 is radiated to the ground by the underground heat exchanger 23.

  In the terminal circulation circuit 30, the circulating liquid L that has flowed into the first heat exchanger 41 by the circulating liquid circulation pump 32 is heated in the first heat exchanger 41 that functions as an evaporator. In the second heat exchanger 51 functioning as an evaporator, the air heat source heat exchanger in the second heat exchanger 51 after being cooled by performing heat exchange with the first refrigerant C1 that has been heat-exchanged with the medium H1 and cooled as described above. At 55, heat is exchanged with the outside air, and heat is exchanged with the second refrigerant C2 cooled as described above to further cool. The circulating fluid L thus cooled is then supplied to the heat exchange terminal 36 to cool the air-conditioned space.

  In addition, in the above, although the state at the time of the air_conditionaing | cooling operation which operated both the underground heat pump unit 4 and the air heat pump unit 5 was demonstrated and demonstrated in FIG. 4, it is not restricted to this. That is, a cooling operation in which only the geothermal heat pump unit 4 is operated or a cooling operation in which only the air heat heat pump unit 5 is operated is possible.

  Next, the underground heat control device 61 and the air heat control device 62 will be described. Although not shown in detail, the underground heat control device 61 and the air heat control device 62 include a storage unit that stores various data and programs, and a control unit that performs calculation / control processing. First, functional configurations of the underground heat control device 61 and the air heat control device 62 during heating operation will be described with reference to FIG.

  As shown in FIG. 5, the underground heat control device 61 functionally includes a compressor control unit 61A, an expansion valve control unit 61B, and a pump control unit 61C. The underground heat control device 61 is communicably connected to the terminal control device 36a and the main remote controller 60a provided in each of the heat exchange terminals 36 (see FIG. 2).

  The compressor control unit 61A includes a switching control unit 61p (details will be described later). The temperature of the circulating fluid L (warm water) detected by the return fluid temperature sensor 34 (hereinafter referred to as “return warm water temperature” as appropriate). The rotation speed of the first compressor 43 is controlled according to FIG. Particularly in this example, the compressor control unit 61A determines that the return hot water temperature of the circulating fluid L detected by the return liquid temperature sensor 34 becomes a desired target return hot water temperature corresponding to the operation of the main remote controller 60a, for example. Thus, the rotation speed of the first compressor 43 is controlled.

  The expansion valve control unit 61B controls the valve opening degree of the first expansion valve 44 according to the refrigerant discharge temperature of the first refrigerant C1 detected by the first refrigerant discharge temperature sensor 42a. In particular, in this example, the expansion valve control unit 61B determines that the refrigerant discharge temperature of the first refrigerant C1 detected by the first refrigerant discharge temperature sensor 42a becomes a control target temperature corresponding to, for example, the operation of the main remote controller 60a. Thus, the valve opening degree of the first expansion valve 44 is controlled.

  The pump control unit 61C detects the temperature of the first refrigerant C1 detected by the first refrigerant temperature sensor 42b (at this time, the underground heat source heat exchanger 45 functions as an evaporator. The rotation speed of the underground heat circulation pump 22 is controlled according to the temperature) (see also FIG. 2). Particularly in this example, the pump control unit 61C is configured so that the temperature of the evaporator inlet refrigerant of the first refrigerant C1 detected by the first refrigerant temperature sensor 42b becomes a substantially constant value. The number of revolutions is controlled.

  The air heat controller 62 functionally includes a compressor controller 62A, an expansion valve controller 62B, and a fan controller 62C. The air heat control device 62 is communicably connected to the underground heat control device 61 (see FIG. 2).

  The compressor control unit 62A includes a switching control unit 62p (details will be described later), and the second compressor 53 according to the return hot water temperature (see FIG. 3) detected by the return liquid temperature sensor 34. Control the number of revolutions. In particular, in this example, the compressor control unit 62A determines that the return hot water temperature detected by the return liquid temperature sensor 34 is, for example, a desired target return hot water temperature corresponding to the operation of the main remote controller 60a. 2 The rotational speed of the compressor 53 is controlled. The compressor control unit 62A of the air heat control device 62 and the compressor control unit 61A of the underground air heat control device 61 cooperate with each other as necessary, and are the target first compressor 43. Alternatively, the second compressor 53 is controlled.

  The expansion valve control unit 62B controls the valve opening degree of the second expansion valve 54 in accordance with the refrigerant discharge temperature of the second refrigerant C2 detected by the second refrigerant discharge temperature sensor 52a. In particular, in this example, the expansion valve control unit 62B determines that the refrigerant discharge temperature of the second refrigerant C2 detected by the second refrigerant discharge temperature sensor 52a is a control target temperature corresponding to, for example, the operation of the main remote controller 60a. Thus, the valve opening degree of the second expansion valve 54 is controlled. The expansion valve control unit 62B of the air heat control device 62 and the expansion valve control unit 61B of the underground air heat control device 61 cooperate with each other as necessary, and are the target first expansion valve 44. Alternatively, the second expansion valve 54 is controlled.

  The fan control unit 62C controls the rotational speed of the blower fan 56 according to the temperature of the outside air detected by the outside air temperature sensor 57 (see also FIG. 2).

  In the above description with reference to FIG. 5, the description has been made based on the input / output of information during the heating operation. However, during the cooling operation, as shown in FIG. 6, the underground heat control device 61 and the air heat control device 62 The content of the input / output information is different with the configuration unchanged. That is, the temperature of the circulating liquid L detected by the return liquid temperature sensor 34 is a so-called cold water temperature (hereinafter referred to as “return cold water temperature”, refer to FIG. 4 as appropriate), and this return cold water temperature is the compressor control unit 61A, 62A is input. Further, the compressor control units 61A and 62A are configured so that the return chilled water temperature detected by the return liquid temperature sensor 34 is, for example, the desired return chilled water temperature corresponding to the operation of the main remote controller 60a. The number of rotations of the compressor 43 and the second compressor 53 is controlled. Further, the temperature of the refrigerant C1 detected by the first refrigerant temperature sensor 42b, that is, the condenser outlet refrigerant temperature (at this time, the underground heat source heat exchanger 45 functions as a condenser) is input to the pump control unit 61C. The

  In the heat pump device 1 having the above basic configuration and operation, the main part of the present embodiment is the switching control newly provided in the compressor control units 61A and 62A on the ground heat control device 61 and the air heat control device 62 side, respectively. Control contents for the first and second compressors 43 and 53 by the units 61p and 62p (details will be described later) (switching control of the main power source / auxiliary power source to the first and second compressors 43 and 53 and increase in the rotational speed) Control, details are given later). Hereinafter, the details will be described in order.

  First, as described above, the heat pump device 1 according to the present embodiment uses the two heat sources of the ground heat source and the air heat source in combination, but how to efficiently combine and use these different heat sources (in other words, paraphrase) For example, it is important to determine how to switch and combine the underground heat source and the air heat source. However, the outdoor air that is a fluid (gas phase) and the soil in the ground that is a solid (solid phase) are greatly different in characteristics and handling as a heat source. For example, outdoor air has a large temperature change in summer and winter, while the temperature in the ground is small throughout the year. Although all heat sources have a large heat capacity, outdoor air has a high heat transfer rate and can be circulated by blowing with a fan, while underground soil has a low heat transfer rate and is fixed. Cannot be circulated. For this reason, outdoor air is easy to detect the temperature in the whole outside air, but the temperature in the whole earth is difficult to detect because the temperature distribution in the soil in the ground tends to be locally localized.

  From the above, first, in the present embodiment, the switching and combination of the air heat source and the underground heat source are determined based on the outside air temperature. That is, based on the outside air temperature detected by the outside air temperature sensor 57 (see FIGS. 5 and 6), the switching control units 61p and 62p as the control means provided in the compressor control units 61 and 62 cooperate with each other. In the terminal circulation circuit 30 capable of performing both heat exchange in the first heat exchanger 41 and heat exchange in the second heat exchanger 51, which heat exchange is the main and which heat exchange is the auxiliary Switch.

  For example, during cooling operation, as shown in FIG. 7 (a), when the outside air temperature is not so high, such as in spring or autumn (in this example, less than 30 ° C. or less than 35 ° C., which will be described later) Therefore, the second compressor 53 using an air heat source is preferentially driven as a main power source, and the first compressor 43 using a ground heat source is driven as an auxiliary power source. .

  On the contrary, when the outside air temperature is relatively high in summer or the like (in this example, 30 ° C. or more or 35 ° C. or more, which will be described later), since the heat radiation to the outside air cannot be expected so much, The first compressor 43 is preferentially driven as a main power source, and the second compressor 53 using an air heat source is driven as an auxiliary power source.

  That is, in this embodiment, when starting the cooling operation, first, if the outside air temperature is less than 30 ° C. as the reference temperature, the second compressor 53 of the air heat heat pump circuit 50 is used as the main power source, The cooling operation is started using the first compressor 43 of the underground heat pump circuit 40 as an auxiliary power source. If the outside air temperature is 30 ° C. or more as the reference temperature, the first compressor 43 of the geothermal heat pump circuit 40 is used as a main power source, and the second compressor 53 of the air heat heat pump circuit 50 is used as auxiliary power. The cooling operation is started as a source.

  In the present embodiment, after the cooling operation is started as described above, when the outside air temperature changes, the main power source and the auxiliary power source are appropriately switched according to the degree of the change.

  That is, after the operation is started with the second compressor 53 as the main power source and the first compressor 43 as the auxiliary power source (the outside air temperature at the start of the cooling operation is less than 30 ° C.), as shown in FIG. The second compressor 53 is used as a main power source as it is and the first compressor 43 is used as an auxiliary power source until the outside air temperature rises to 35 [° C.] or higher which is a reference temperature (less than 35 [° C.]). And Thereafter, when the outside air temperature rises to 35 [° C.] or higher, the air heat heat pump circuit using the first compressor 43 of the geothermal heat pump circuit 40 that uses a geothermal heat source as a main power source and an air heat source. 50 second compressors 53 are used as auxiliary power sources.

  Conversely, after the first compressor 43 is started as the main power source and the second compressor 53 is the auxiliary power source (when the outside air temperature at the start of the cooling operation is 30 ° C. or higher), as shown in FIG. The first compressor 43 is used as a main power source and the second compressor 53 is used as an auxiliary power source as long as the outside air temperature does not fall below 30 [° C.] (in the case of 30 [° C.] or higher). Thereafter, when the outside air temperature falls below 30 [° C.], the ground heat heat pump circuit using the second compressor 53 of the air heat heat pump circuit 50 using an air heat source as a main power source and using a ground heat source. Forty first compressors 43 are used as auxiliary power sources.

  That is, as indicated by the arrows in FIG. 8, in the direction of the increase in the outside air temperature as described above, the reference temperature serving as a delimiter for switching between the main power source and the auxiliary power source is set to 35 [° C.], while the outside air temperature is decreased. In the direction, the reference temperature is changed to 30 [° C.] (= the switching behavior of the main power source / auxiliary power source is provided with hysteresis).

  Further, for example, during heating operation, as shown in FIG. 7B, when the outside air temperature is relatively low in winter or the like (in this example, less than 2 ° C. or less than 5 ° C., described later), heat is absorbed from the outside air. As a result, there is a problem that the air heat source heat exchanger 55 is frosted, so that the first compressor 43 is preferentially driven as a main power source, and the second compressor 53 is driven as an auxiliary power source.

  On the other hand, when the outside air temperature is not so low (eg, 2 ° C. or more or 5 ° C. or more in this example, which will be described later) in autumn or spring, the air heat source heat exchanger 55 is frosted even if it absorbs heat from outside air. Since it is difficult, the second compressor 53 is preferentially driven as a main power source, and the first compressor 43 is driven as an auxiliary power source.

  That is, in this embodiment, when starting the heating operation, first, if the outside air temperature is less than 5 ° C. as the reference temperature, the first compressor 43 of the geothermal heat pump circuit 40 is used as the main power source. The heating operation is started using the second compressor 53 of the air heat heat pump circuit 50 as an auxiliary power source. If the outside air temperature is 5 ° C. or more as the reference temperature, the second compressor 53 of the air heat heat pump circuit 50 is used as a main power source, and the first compressor 43 of the underground heat pump circuit 40 is used as auxiliary power. As a source, heating operation is started.

  In the present embodiment, after the heating operation is started as described above, when the outside air temperature changes, the main power source and the auxiliary power source are appropriately switched according to the degree of the change.

  That is, after starting operation with the first compressor 43 as the main power source and the second compressor 53 as the auxiliary power source (the outside air temperature at the start of heating operation is less than 5 ° C.), as shown in FIG. The first compressor 43 is used as a main power source and the second compressor 53 is used as an auxiliary power source until the outside air temperature rises to a reference temperature of 5 [° C.] or higher (less than 5 [° C.]). And After that, when the outside air temperature rises to 5 [° C.] or more, the ground heat heat pump circuit using the second compressor 53 of the air heat heat pump circuit 50 using an air heat source as a main power source and using a ground heat source. Forty first compressors 43 are used as auxiliary power sources.

  Conversely, after the operation is started with the second compressor 53 as the main power source and the first compressor 43 as the auxiliary power source (when the outside air temperature at the start of heating operation is 5 ° C. or higher), as shown in FIG. The second compressor 53 is used as a main power source and the first compressor 43 is used as an auxiliary power source as long as the outside air temperature does not fall below 2 [° C.] (in the case of 2 [° C.] or higher). Thereafter, when the outside air temperature falls below 2 [° C.], the air heat heat pump circuit using the first compressor 43 of the geothermal heat pump circuit 40 that uses a geothermal heat source as a main power source and an air heat source. 50 second compressors 53 are used as auxiliary power sources.

  That is, as indicated by an arrow in FIG. 9, in the direction of the increase in the outside air temperature as described above, the reference temperature, which is a delimiter for switching between the main power source and the auxiliary power source, is set to 5 [° C.], while the outside air temperature is decreased. In the direction, the reference temperature is changed to 2 [° C.] (= the switching behavior of the main power source / auxiliary power source has a hysteresis).

  As described above, when the outside air temperature changes and it is considered that it is more efficient to replace the assignment of the main power source and the auxiliary power source up to that point, the first switching control units 61p and 62p perform the first operation. The assignment to the compressor 43 and the second compressor 53 is switched, and the compressor that has been the main power source until then is driven as an auxiliary power source, and the compressor that has been the auxiliary power source is driven as the main power source. Then, each compressor 43 is set so that the return hot water temperature or the return cold water temperature of the circulating liquid L detected by the return liquid temperature sensor 34 becomes a desired target temperature corresponding to the operation of the main remote controller 60a, for example. , 53 (in this example, only the compressor driven as the main power source, see FIGS. 16 and 17 described later) is controlled.

  However, when the main power source and the auxiliary power source are switched as described above, the driving conditions of the compressor that has been driven as the main power source and the driving of the compressor that has been driven as the auxiliary power source until then. It is possible to reverse the conditions. However, when the cooling / heating load happens to increase just before switching between the main power source / auxiliary power source in this way, the actual temperature of the circulating fluid L in the terminal circulation circuit 30 (for example, the return hot water temperature or the return cold water temperature) A large temperature deviation occurs between the target temperature (in the above example, the target return hot water temperature and the target return cold water temperature). Therefore, it takes a long time for the temperature of the circulating fluid L in the terminal circuit 30 to reach the target temperature, which may impair comfort.

  For example, the return hot water temperature (or return cold water temperature) fluctuates abruptly because the actual number of heat exchange terminals 36 increases immediately before the main power source / auxiliary power source is actually switched (FIGS. 11 and FIG. 14) or just before the main power source / auxiliary power source is actually switched, the air conditioning load increases due to the setting temperature changing operation on the main remote controller 60a, and the target return hot water temperature (or the target return cold water temperature) fluctuates rapidly. In the case (see FIGS. 12 and 15 described later), a large temperature deviation occurs between the target return hot water temperature (or target return cold water temperature) and the actual return hot water temperature (or return cold water temperature). .

  In such a case, the outputs of the heat pump units 4 and 5 (in other words, the rotational speeds of the compressors 43 and 53) are adjusted so as to reduce this large temperature deviation. However, as described above, immediately after switching between the main power source / auxiliary power source, the actual return hot water temperature (or return cold water temperature) is brought close to the target return hot water temperature (or target return cold water temperature) to reduce the temperature deviation. It takes a longer time than usual before the air-conditioned space can be air-conditioned at the original temperature.

  Therefore, in this embodiment, a deviation (temperature deviation) between the return hot water temperature (or the return chilled water temperature) detected by the return liquid temperature sensor 34 and the target return hot water temperature (or the target return chilled water temperature) is predetermined. When the threshold value is exceeded, each switching control unit 61p, 62p provided in each compressor control unit 61A, 62A increases the rotational speed of the compressor that becomes the main power source after switching. In particular, in the present embodiment, the temperature deviation is quickly reduced by increasing the rotational speed of the compressor serving as the main power source to the maximum rotational speed.

  Details of the behavior of each heat pump unit by the above control will be described more specifically with reference to FIGS. In the following, the geothermal heat pump unit 4 and the air heat heat pump unit 5 have substantially the same performance and specifications, and the same output is obtained if the rotation speeds of the compressors 43 and 53 are the same. explain.

  First, as an example of the control performed during the heating operation in the heat pump device 1 of the present embodiment, there is no increase / decrease in the actual number of the heat exchange terminals 36, a set temperature changing operation with the main remote controller 60a, etc., and the target return hot water The case where a big deviation does not arise between temperature and actual return hot water temperature is demonstrated with the graph shown in FIG. For comparison with FIGS. 11 to 15 described later, the state (scene) in which this control is executed is denoted as “scene 1” in FIG.

  In FIG. 10, FIG. 10A shows a temporal transition of the outside air temperature [° C.] (detected by the outside air temperature sensor 57 in the above example). FIG. 10B shows the time course of the return hot water temperature [° C.], and the solid line indicates the actually detected return hot water temperature [° C.] (detected by the return liquid temperature sensor 34 in the above example). The broken line indicates the target return hot water temperature [° C.] (in this example, 40 [° C.]). FIG. 10C shows the change over time in the rotational speed [rps] of the first compressor 43 of the geothermal heat pump circuit 40. FIG. 10 (d) shows the time course of the rotational speed [rps] of the second compressor 53 of the air heat heat pump circuit 50.

  In this example, in the state where the outside air temperature is initially 5 [° C.] or higher, the second compressor 53 of the air heat heat pump circuit 50 is used as a main power source, and the first compressor 43 of the underground heat pump circuit 40 is used as auxiliary power. The driving | operation is performed as a source (refer time t1-t2 of Fig.10 (a)). At this time, the rotation speed of the second compressor 53 as the main power source is 60 [rps] (see time t1 to t2 in FIG. 10D), and the rotation of the first compressor 43 as the auxiliary power source. The number is 45 [rps] (see time t1 to t2 in FIG. 10C), and the return hot water temperature is substantially constant at about 40 [° C.], which is substantially equal to the target return hot water temperature. (See time t1 to t2 in FIG. 10B).

  After the above state, when the outside air temperature drops and divides 2 [° C.] (see time t2 in FIG. 10A), the first and second switching control units 61p and 62p trigger the first and second The main power source / auxiliary power source is switched in the compressors 43 and 53. However, at this time, even if it is determined that the switching of the main power source / auxiliary power source is necessary due to a change in the outside air temperature, the switching control units 61p and 62p do not immediately perform the actual switching operation but need to do so. When the state determined to be continued for a predetermined period (30 minutes in this example) (see step S40 in FIG. 16 described later), the switching is performed. This excludes instantaneous fluctuations in the outside air temperature due to accidental factors, such as when the outside air temperature rises for a short time due to a gust of wind, and the switching is performed only in response to a tendency to change in the outside air temperature. This is to ensure the operational stability of the compressors 43 and 53.

  Accordingly, when 30 minutes, which is a predetermined time, has elapsed in the above-described state from the time when the outside air temperature is initially determined to be below 2 [° C.], the main power source / auxiliary power source is switched. That is, the second compressor 53 is switched from the main power source to the auxiliary power source, and the rotation speed thereof is reduced to 45 [rps] (which is the same as the rotation speed of the first compressor 43 so far) (see FIG. 10 (d) (see time t3), the first compressor 43 is switched from the auxiliary power source to the main power source, and the rotation speed thereof is the same as the rotation speed of the second compressor 53 so far. [Rps] (see time t3 in FIG. 10C).

  As described above, in this case, since there is no change in the heating load due to the increase or decrease in the actual number of the heat exchange terminals 36, the set temperature change operation or the like on the main remote controller 60a, etc., the return hot water temperature and the target The return hot water temperature is also maintained substantially constant (without particular fluctuations before and after the switching) (see times t3 to t4 in FIG. 10B).

  Next, an example of control when the number of operating heat exchange terminals 36 changes and the heating load fluctuates during heating operation will be described as “scene 2” with reference to FIG. 11 corresponding to FIG.

  For example, as shown in FIG. 11, the rotational speed of the second compressor 53 is 60 [rps] (see time t1 to t2 in FIG. 11 (d)) as in FIG. After the rotational speed is 45 [rps] (see time t1 to t2 in FIG. 11C), the return hot water temperature and the target return hot water temperature are about 40 [° C.], the outside air temperature drops to 2 [° C.]. Until the predetermined period (30 minutes in the above example) elapses until the state in which the switching control units 61p and 62p determine that the switching of the main power source / auxiliary power source is necessary continues until that time. The operation of the heat exchange terminal 36 that has been stopped may be started. In this case, since the heating load increases due to the increase in the number of heat exchange terminals 36, the return hot water temperature rapidly decreases, and a large deviation occurs from the target return hot water temperature (FIG. 11 (b)). Time t3).

  In the present embodiment, in response to the above, when the deviation between the target return hot water temperature and the return hot water temperature is equal to or higher than a predetermined threshold (4 [° C.] in this example), the switching control unit 61p. , 62p, the rotational speed of the first compressor 43, which is the main power source by the switching, is increased to the maximum rotational speed (90 [rps] in this example) (time in FIG. 11C). t3). As a result, the maximum capacity of the underground heat pump unit 4 on the main power source side is drawn out, the deviation is quickly reduced, and the return hot water temperature is brought close to the target return hot water temperature (see FIG. 11B). The temperature of the air-conditioned space can be set to a desired temperature more quickly. At that time, after the return hot water temperature is recovered to the target return hot water temperature, the deviation is kept small by the normal control (so-called return temperature control) described with reference to FIG. In that case, considering the operational stability of the compressors 43 and 53, the rotational speed of the compressor is increased or decreased step by step at a predetermined time interval. In this case, as described above, the rotational speed of the first compressor 43 that has reached the maximum rotational speed is controlled to be reduced stepwise, and the rotational speed is shifted to 60 [rps] (in FIG. 11C). Time t3-t4).

  Next, during the heating operation, there is an operation for changing the set temperature with the main remote controller 60a, and an example of control when the heating load fluctuates as a result is “scene 3”. 12 will be described.

  Similarly to the above, for example, as shown in FIG. 12, the rotation speed of the second compressor 53 is 60 [rps] (see time t1 to t2 in FIG. 12D), and the rotation speed of the first compressor 43 is 45 [rps] (see time t1 to t2 in FIG. 12C), after the return hot water temperature and the target return hot water temperature are about 40 [° C.], the outside air temperature drops to 2 [° C.], and switching control Before the predetermined period (30 minutes in the above example) elapses after the state in which the switching of the main power source / auxiliary power source is determined to be necessary by the units 61p and 62p, the main remote controller 60a The target return hot water temperature may increase due to a change (increase) operation of the set temperature. Also in this case, as in FIG. 11, the heating load increases due to the increase in the target return hot water temperature, so that a large deviation occurs from the actual target return hot water temperature (in FIG. 12B). Time t3).

  The present embodiment can also cope with this case, and, similarly to the above, when the deviation between the target return hot water temperature and the return hot water temperature is equal to or higher than the threshold (4 [° C.]), the switching control unit Under the control of 61p and 62p, the rotational speed of the first compressor 43 serving as the main power source by the switching increases to the maximum rotational speed (90 [rps] in this example) (see FIG. 12C). See immediately after time t3). As a result, as described above, the maximum capacity of the geothermal heat pump unit 4 is drawn out, and the return hot water temperature is rapidly increased rapidly to approach the target return hot water temperature to reduce the deviation (time of FIG. 12 (b)). t3 to t4), the temperature of the air-conditioned space can be set to a desired temperature earlier. As described above, after the return hot water temperature reaches the target return hot water temperature, the deviation is kept small by normal return temperature control. As described above, the rotational speed of the first compressor 43 that has reached the maximum rotational speed is controlled to be reduced stepwise and shifts to the rotational speed 60 [rps] (see times t3 to t4 in FIG. 12C). .

  In the above description, the heating operation is described as an example, but in the present embodiment, the same control is executed even during the cooling operation. First, as an example of control performed at the time of cooling operation in the heat pump device 1 of the present embodiment, increase / decrease in the number of actual operation of the heat exchange terminal 36, setting temperature change operation with the main remote controller 60a, etc., as in FIG. The case where there is no large deviation between the target return hot water temperature and the actual return hot water temperature will be described as “scene 4” with reference to the graph shown in FIG.

  In the drawing, FIG. 13A shows the time course of the outside air temperature [° C.] (detected by the outside air temperature sensor 57 in the above example), as in FIG. 10A. FIG. 13B shows the time course of the return chilled water temperature [° C.], and the solid line shows the actually detected return chilled water temperature [° C.] (detected by the return liquid temperature sensor 34 in the above example). The broken line indicates the target return cold water temperature [° C.] (in this example, 15 [° C.]). Moreover, FIG.13 (c) has shown the time-dependent transition of the rotation speed [rps] of the said 1st compressor 43 of the said geothermal heat pump circuit 40 similarly to the said FIG.10 (c). FIG. 13D shows the change over time in the rotational speed [rps] of the second compressor 53 of the air heat heat pump circuit 50, as in FIG. 10D.

  In this example, in the state where the outside air temperature is initially lower than 30 [° C.], the second compressor 53 of the air heat heat pump circuit 50 is used as a main power source, and the first compressor 43 of the underground heat pump circuit 40 is assisted. The driving | operation is performed as a motive power source (refer time t1-t2 of Fig.13 (a)). At this time, the rotation speed of the second compressor 53 as the main power source is 60 [rps] (see time t1 to t2 in FIG. 13D), and the rotation of the first compressor 43 as the auxiliary power source. The number is 45 [rps] (see time t1 to t2 in FIG. 13C), and the return chilled water temperature is substantially equal to about 15 [° C.], which is substantially equal to the target return chilled water temperature. (See time t1 to t2 in FIG. 13B).

  After the above state, when the outside air temperature rises and exceeds 35 [° C.] (see time t2 in FIG. 13A), the switching control units 61p and 62p use the first and second as a trigger. The main power source / auxiliary power source is switched in the compressors 43 and 53. However, at this time, as described above, in order to exclude instantaneous fluctuations in the outside air temperature and to ensure the operational stability of the compressors 43 and 53, the switching control units 61p and 62p cause the main power to change according to a change in the outside air temperature. When the state in which it is determined that the source / auxiliary power source needs to be switched continues for a predetermined period (30 minutes in this example) (see step S140 in FIG. 17 described later), the switching is performed.

  That is, when 30 minutes, which is a predetermined time, has elapsed in the above state from the time when it is determined that the outside air temperature has first exceeded 35 [° C.], the second compressor 53 is switched from the main power source to the auxiliary power source. The rotational speed is reduced to 45 [rps] (same as the rotational speed of the first compressor 43 so far) (see time t3 in FIG. 13 (d)), and the first compressor 43 is supplied with auxiliary power. Switching from the power source to the main power source increases the rotational speed to 60 [rps] (same as the rotational speed of the second compressor 53 so far) (see time t3 in FIG. 13C).

  As in the above case, in this case, there is no change in the cooling load due to the increase or decrease in the actual number of the heat exchange terminals 36, the operation of changing the set temperature with the main remote controller 60a, etc., so the return cold water temperature and the target return The chilled water temperature is also maintained substantially constant (without particular fluctuations before and after the switching) (see times t3 to t4 in FIG. 13B).

  Next, an example of control when the number of operating heat exchange terminals 36 changes and the cooling load fluctuates during cooling operation will be described as “scene 5” with reference to FIG. 14 corresponding to FIG.

  For example, as shown in FIG. 14, as in FIG. 13, the rotation speed of the second compressor 53 is 60 [rps] (see time t <b> 1 to t <b> 2 in FIG. 14D), and the first compressor 43 After the rotation speed is 45 [rps] (see time t1 to t2 in FIG. 14C), the return hot water temperature and the target return cold water temperature are about 15 [° C.], the outside air temperature rises to 35 [° C.]. Before the predetermined period (30 minutes in the above example) elapses after the switching control units 61p and 62p continue to determine that the switching of the main power source / auxiliary power source is necessary, Similarly to 11, the operation of the heat exchange terminal 36 that has been stopped may be started. In this case, since the cooling load increases due to the increase in the number of heat exchange terminals 36, the return chilled water temperature rises rapidly, and a large deviation occurs from the target return chilled water temperature (FIG. 14B). Time t3).

  In the present embodiment, in response to the above, when the deviation between the target return chilled water temperature and the return chilled water temperature is equal to or higher than a predetermined threshold value (4 [° C.] in this example), the switching control unit Under the control of 61p and 62p, the rotational speed of the first compressor 43 serving as the main power source by the switching is increased to the maximum rotational speed (90 [rps] in this example) (see FIG. 14C). Time t3). As a result, as described above, the maximum capacity of the underground heat pump unit 4 on the main power source side is extracted, the deviation is quickly reduced, and the return chilled water temperature is brought closer to the target return chilled water temperature to be restored (FIG. 14). (Refer to time t3 to t4 in (b)), the temperature of the air-conditioned space can be set to a desired temperature earlier. At that time, after the return chilled water temperature is lowered to the target return chilled water temperature, the deviation is kept small by the normal control (so-called return temperature control) described with reference to FIG. In that case, considering the operational stability of the compressors 43 and 53, the rotational speed of the compressor is increased or decreased step by step at a predetermined time interval. In this case, as described above, the rotational speed of the first compressor 43 that has reached the maximum rotational speed is controlled to be reduced stepwise, and the rotational speed is shifted to 60 [rps] (in FIG. 14C). Time t3-t4).

  Next, during cooling operation, there is an operation for changing the set temperature with the main remote controller 60a, and as a result, the example of control when the cooling load fluctuates is referred to as “scene 6”, which corresponds to FIG. 13 and FIG. 15 will be described.

  Similarly to the above, for example, as shown in FIG. 15, the rotation speed of the second compressor 53 is 60 [rps] (see time t1 to t2 in FIG. 15D), and the rotation speed of the first compressor 43 is 45 [rps] (see time t1 to t2 in FIG. 15C), after the return chilled water temperature and the target return chilled water temperature are about 15 [° C.], the outside air temperature rises to 35 [° C.], and switching control Before the predetermined period (30 minutes in the above example) elapses after the state in which the switching of the main power source / auxiliary power source is determined to be necessary by the units 61p and 62p, the main remote controller 60a The target return chilled water temperature may decrease due to a change (decrease) in the set temperature. Also in this case, as in FIG. 14, the cooling load increases due to the decrease in the target return chilled water temperature, so that a large deviation occurs from the actual target return chilled water temperature (see FIG. 15B). Time t3).

  The present embodiment can also cope with this case, and similarly to the above, when the deviation between the target return chilled water temperature and the return chilled water temperature is equal to or higher than the threshold (4 [° C.]), the switching control unit Under the control of 61p and 62p, the rotational speed of the first compressor 43 serving as the main power source by the switching increases to the maximum rotational speed (90 [rps] in this example) (see FIG. 15C). See immediately after time t3). As a result, as described above, the maximum capacity of the geothermal heat pump unit 4 is drawn out, and the return hot water temperature is rapidly lowered to approach the target return cold water temperature to reduce the deviation (time of FIG. 15 (b)). t3 to t4), the temperature of the air-conditioned space can be set to a desired temperature earlier. As described above, after the return chilled water temperature reaches the target return chilled water temperature, the deviation is kept small by normal return temperature control. As described above, the rotational speed of the first compressor 43 that has reached the maximum rotational speed is subjected to reduction control in stages, and shifts to the rotational speed 60 [rps] (see times t3 to t4 in FIG. 15C). .

  Next, a control procedure executed by the switching control units 61p and 62p in cooperation to realize the above method will be described with reference to the flowcharts of FIGS.

  First, the control procedure during heating operation is shown in FIG. In FIG. 16, first, in step S10, the switching controllers 61p and 62p determine whether or not the heat pump device 1 has entered an operation start state. Specifically, the operation start state is, for example, when the operation is started from the stop state by an appropriate operation start operation of the heat pump device 1 by the operator, or after restarting the operation, the heat pump device is restarted 1 is started again (details will be described later). Until the operation start state is reached, the determination in step S10 is not satisfied (S10: No), and the loop waits. When the operation start state is established, the determination in step S10 is satisfied (S10: Yes), and the process proceeds to step S12.

  In step S12, the switching control units 61p and 62p mainly use either the compressor 43 of the first underground heat pump circuit 40 or the second compressor 53 of the air heat heat pump circuit 50 when starting the heating operation. The power source is set and which is used as the auxiliary power source. That is, if the outside air temperature detected by the outside air temperature sensor 57 is lower than the reference temperature (5 ° C. in the above example), the first compressor 43 is used as a main power source and the second compressor 53 is used. Heating operation is started as an auxiliary power source. If the outside air temperature is equal to or higher than the reference temperature (5 ° C.), the heating operation is started using the second compressor 53 as a main power source and the first compressor 43 as an auxiliary power source. Thereafter, the process proceeds to step S15.

  In step S15, the switching control units 61p and 62p determine whether or not the heat pump device 1 is in an operation end state. That is, when the heating operation is performed under the control of the rotation speed as described later and the heating load is reduced, the circulation detected by the return liquid temperature sensor 34 of the terminal circulation circuit 30 without operating the heat pump device 1. The return hot water temperature of the liquid L may reach the target return hot water temperature or higher. In this case, the heat pump device 1 is stopped by a known control by the underground heat control device 61 and the air heat control device 62 and enters a standby state (that is, the operation of the heat pump device 1 is once ended). In step S15, the switching controllers 61p and 62p determine whether or not the heat pump apparatus 1 has entered this standby state. If it is in the operation end state (that is, the standby state), the determination in step S15 is satisfied (S15: YES), and this flow is ended. On the other hand, the determination in step S15 is not satisfied while the operation is not finished (that is, in the standby state) (S15: NO), and the process proceeds to step S20.

  In step S20, the switching controllers 61p and 62p determine whether or not the return hot water temperature detected from the return liquid temperature sensor 34 at this time is lower than the target return hot water temperature (40 [° C.] in the above example). Determine. If the return hot water temperature is lower than the target return hot water temperature, the determination is satisfied (S20: YES), and the routine goes to Step S25.

  In step S25, the switching controllers 61p and 62p increase the rotational speed of the compressor that is the main power source at this time. The number of rotations of the compressor of the main power source is not limited to increase, and the number of rotations of the compressor of the auxiliary power source may be increased as appropriate. Thereafter, the process proceeds to step S35 described later.

  On the other hand, in the determination in step S20, if the return hot water temperature is equal to or higher than the target return hot water temperature, the determination is not satisfied (S20: NO), and the process proceeds to step S30.

  In step S30, the switching controllers 61p and 62p reduce the rotational speed of the compressor that is the main power source at this time. The number of rotations of the compressor of the main power source is not limited, and the number of rotations of the compressor of the auxiliary power source may be reduced as appropriate. Thereafter, the process proceeds to step S35.

  In step S35, the switching control units 61p and 62p perform the reference temperature shown in FIG. 9 (5 [° C.] in the increasing direction of the outside temperature and 2 [° C.] in the decreasing direction, with respect to the outside temperature detected by the outside temperature sensor 57). C]]), it is determined whether or not switching of the main power source / auxiliary power source is necessary. If switching of the main power source / auxiliary power source is not necessary, the determination is not satisfied (S35: NO), and the same procedure is repeated by returning to step S15.

  On the other hand, when the main power source / auxiliary power source needs to be switched, the determination is satisfied (S35: YES), and the routine goes to Step S40.

  In step S40, the switching controllers 61p and 62p determine whether or not 30 minutes as the predetermined period have elapsed. As long as 30 minutes have not elapsed, the determination is not satisfied (S40: NO), and the process returns to step S35 and the same procedure is repeated. If 30 minutes have elapsed, the determination is satisfied (S40: YES), and the routine goes to Step S50.

  In step S50, the switching control units 61p and 62p switch the compressor that was the main power source at this time to the rotational speed as the auxiliary power source, and the compressor that was the auxiliary power source at this time is the main power source. Switch to the number of revolutions. 10 to 12, when the geothermal heat pump unit 4 and the air heat heat pump unit 5 have substantially the same performance and specifications (if the rotation speeds of the compressors 43 and 53 are the same, the outputs are the same. As an example, the case where the rotation speeds of each other are simply exchanged has been described. However, when the performance and specifications of the heat pump units 4 and 5 are different (the heating output with respect to the rotation speeds of the compressors 43 and 53 is different). If they are different from each other), the heating output is switched to the corresponding number of revolutions so as to exchange each other. Thereafter, the process proceeds to step S55.

  In step S55, the switching control units 61p and 62p calculate a deviation between the value of the target return hot water temperature set at this time and the return hot water temperature detected by the return liquid temperature sensor 34 at this time, It is determined whether the magnitude (absolute value) of this deviation is 4 [° C.] or more. If it is less than 4 [° C.], the determination is not satisfied (S55: NO), and the process returns to step S15 and the same procedure is repeated.

  On the other hand, when the magnitude of the deviation is 4 [° C.] or more, the determination is satisfied (S55: YES), and the routine goes to Step S60.

  In step S60, the switching controllers 61p and 62p increase the rotational speed of the compressor that is the main power source at this time (in this example, increase the maximum rotational speed). Then, it returns to said step S15 and repeats the same procedure.

  As described above, by the processing of step S20, step S25, and step S30, the compressor of the main power source (and the auxiliary power source of the auxiliary power source if necessary) so that the return hot water temperature matches the target return hot water temperature. The normal return hot water temperature control for controlling the rotation speed of the compressor) is performed, and the switching control of the main power source / auxiliary power source is performed by the processing of step S35 to step S50, and the processing of step S55 and step S60 is performed. Maximum output control on the main power source side is performed based on a deviation between the return hot water temperature and the target return hot water temperature.

  Next, the control procedure during the cooling operation is shown in FIG. In FIG. 17, first, in step S110, the switching control units 61p and 62p determine whether or not the heat pump device 1 has entered the operation start state, similar to step S10 of FIG. Until the operation start state is reached, the determination in step S110 is not satisfied (S110: No), and the loop waits. When the operation start state is established, the determination in step S110 is satisfied (S110: Yes), and the process proceeds to step S112.

  In step S112, the switching control units 61p and 62p mainly use either the compressor 43 of the first underground heat pump circuit 40 or the second compressor 53 of the air heat heat pump circuit 50 when starting the cooling operation. The power source is set and which is used as the auxiliary power source. That is, if the outside temperature detected by the outside temperature sensor 57 is equal to or higher than the reference temperature (30 ° C. in the above example), the first compressor 43 is used as a main power source and the second compressor 53 is used. Cooling operation is started as an auxiliary power source. If the outside air temperature is lower than the reference temperature (30 ° C.), the cooling operation is started using the second compressor 53 as a main power source and the first compressor 43 as an auxiliary power source. Thereafter, the process proceeds to step S115.

  In step S115, the switching control units 61p and 62p determine whether or not the heat pump device 1 is in an operation-finished state, similar to step S15 in FIG. That is, when the cooling operation is performed under the control of the rotation speed as described later and the cooling load is reduced, the circulation detected by the return liquid temperature sensor 34 of the terminal circulation circuit 30 without operating the heat pump device 1. The return chilled water temperature of the liquid L may be equal to or lower than the target return chilled water temperature. In this case, the heat pump device 1 is stopped by a known control by the underground heat control device 61 and the air heat control device 62 and enters a standby state (that is, the operation of the heat pump device 1 is once ended). In step S115, the switching controllers 61p and 62p determine whether or not the heat pump apparatus 1 has entered this standby state. If the operation has been completed, the determination in step S115 is satisfied (S115: YES), and this flow ends. On the other hand, while the operation is not finished, the determination in step S115 is not satisfied (S115: NO), and the process proceeds to step S120.

  In step S120, the switching controllers 61p and 62p determine whether or not the return chilled water temperature detected from the return liquid temperature sensor 34 at this time exceeds the target return chilled water temperature (15 [° C.] in the above example). Determine. If the return chilled water temperature exceeds the target return chilled water temperature, the determination is satisfied (S120: YES), and the routine goes to Step S125.

  In step S125, the switching controllers 61p and 62p increase the rotational speed of the compressor that is the main power source at this time, as in step S25 of FIG. As described above, the number of rotations of the compressor of the main power source is not limited to an increase, and the number of rotations of the compressor of the auxiliary power source may be increased as appropriate. Thereafter, the process proceeds to step S135 described later.

  On the other hand, in the determination in step S120, if the return chilled water temperature is equal to or lower than the target return chilled water temperature, the determination is not satisfied (S120: NO), and the process proceeds to step S130.

  In step S130, the switching controllers 61p and 62p reduce the rotational speed of the compressor that is the main power source at this time, as in step S30 of FIG. The number of rotations of the compressor of the main power source is not limited, and the number of rotations of the compressor of the auxiliary power source may be reduced as appropriate. Thereafter, the process proceeds to step S135.

  In step S135, the switching control units 61p and 62p perform the reference temperature shown in FIG. 10 (35 [° C.] in the increasing direction of the outside temperature and 30 [° C.] in the decreasing direction, with respect to the outside temperature detected by the outside temperature sensor 57. C]]), it is determined whether or not switching of the main power source / auxiliary power source is necessary. If switching of the main power source / auxiliary power source is not necessary, the determination is not satisfied (S135: NO), and the same procedure is repeated by returning to step S115.

  On the other hand, when the main power source / auxiliary power source needs to be switched, the determination is satisfied (S135: YES), and the routine goes to Step S140.

  In step S140, the switching controllers 61p and 62p determine whether or not 30 minutes as the predetermined period have elapsed. As long as 30 minutes have not elapsed, the determination is not satisfied (S140: NO), and the process returns to step S135 and the same procedure is repeated. If 30 minutes have elapsed, the determination is satisfied (S140: YES), and the routine goes to Step S150.

  In step S150, the switching control units 61p and 62p switch the compressor, which is the main power source at this time, to the rotational speed as the auxiliary power source at the same time as in step S50 of FIG. The compressor that was the source is switched to the rotational speed as the main power source. 13 to 15, when the geothermal heat pump unit 4 and the air heat heat pump unit 5 have substantially the same performance and specifications (if the rotation speeds of the compressors 43 and 53 are the same, the outputs are the same. As an example, the case where the rotational speeds of the compressors are simply exchanged has been described. However, when the performance and specifications of the heat pump units 4 and 5 are different (the cooling output for the rotational speeds of the compressors 43 and 53 is different). If they are different from each other), the cooling outputs are respectively switched to the corresponding rotational speeds so as to exchange each other. Thereafter, the process proceeds to step S155.

  In step S155, the switching controllers 61p and 62p calculate a deviation between the target return chilled water temperature set at this time and the return chilled water temperature detected by the return liquid temperature sensor 34 at this time, It is determined whether the magnitude (absolute value) of this deviation is 4 [° C.] or more. If it is less than 4 [° C.], the determination is not satisfied (S155: NO), and the process returns to step S115 and the same procedure is repeated.

  On the other hand, when the magnitude of the deviation is 4 [° C.] or more, the determination is satisfied (S155: YES), and the routine goes to Step S160.

  In step S160, the switching control units 61p and 62p increase the rotational speed of the compressor that is the main power source at this time (in this example, increase it to the maximum rotational speed) as in step S60 of FIG. ). Thereafter, the process returns to step S115 and the same procedure is repeated.

  As described above, by the processing of step S120, step S125, and step S130, the compressor of the main power source (and the auxiliary power source of the auxiliary power source if necessary) so that the return chilled water temperature matches the target return chilled water temperature. The normal return chilled water temperature control for controlling the rotation speed of the compressor) is performed, and the switching control of the main power source / auxiliary power source is performed by the processing of step S135 to step S150, and the processing of step S155 and step S160 is performed. Maximum output control on the main power source side is performed based on a deviation between the return chilled water temperature and the target return chilled water temperature.

  As described above, according to the heat pump device 1 of the present embodiment, the return liquid temperature sensor 34 is provided, and the return hot water temperature (during heating operation) flowing into the first heat exchanger 41 in the terminal circulation circuit 30 or Return chilled water temperature (during cooling operation) is detected. A deviation (specifically, an absolute value) between the detected return hot water temperature (or the return chilled water temperature) and the target return hot water temperature (or the target return chilled water temperature) is a predetermined threshold value (in the example described above). In the case of 4 [° C.] or higher, the rotation speed of the compressor serving as the main power source after the switching of the main power source / auxiliary power source is controlled by the control of each switching control unit 61p, 62p. Increase. Thereby, the temperature deviation between the return hot water temperature (or the return chilled water temperature) and the target return hot water temperature (or the target return chilled water temperature) can be quickly reduced, and comfort is not impaired.

  In the present embodiment, particularly, each switching control unit 61p, 62p switches between the main power source and the auxiliary power source based on the outside air temperature detected by the outside air temperature sensor 57. Thereby, efficient heat exchange can be achieved reliably.

  In the present embodiment, in particular, it waits for a certain amount of time (30 minutes as the predetermined time) to continue for a change in the outside air temperature that requires switching between the main power source and the auxiliary power source. As a result, it is possible to reliably determine that the main power source / auxiliary power source needs to be switched.

  Further, in the present embodiment, in particular, when the compressor of the main power source and the compressor of the auxiliary power source are switched as described above, the number of the heat exchange terminals 36 is increased by an operator operation or the like. When a large temperature deviation occurs between the return hot water temperature (or the return chilled water temperature) and the target return hot water temperature (or the target return chilled water temperature) (see FIGS. 11 and 14). In this case, the state can be quickly eliminated and the temperature deviation can be quickly reduced.

  Further, particularly in the present embodiment, when the compressor of the main power source and the compressor of the auxiliary power source are switched as described above, the target return hot water temperature or the target return cold water temperature happens to be in accordance with an operator's instruction. When a large temperature deviation occurs between the return hot water temperature (or the return chilled water temperature) and the target return hot water temperature (or the target return chilled water temperature) due to the change of Also in FIG. 15), the state can be quickly resolved and the temperature deviation can be quickly reduced.

  In the present embodiment, in particular, the rotation speed of the compressor serving as the main power source is increased to the maximum speed after switching between the main power source / auxiliary power source by the control of each switching control unit 61p, 62p. . Thereby, the temperature deviation between the return hot water temperature (or the return chilled water temperature) and the target return hot water temperature (or the target return chilled water temperature) can be reduced the earliest, and it is ensured that comfort is impaired. Can be prevented.

  In addition, this invention is not limited to the said embodiment, A various change is possible in the range which does not change the summary of invention. For example, in the above-described embodiment, a ground heat exchanger 23 is provided in the ground or the relatively large capacity water source, and the ground heat exchanger 23 exchanges heat with the ground or the water source. Although H1 was circulated in the underground heat circulation circuit 20, it is not restricted to this. That is, instead of configuring such a circulation circuit, an open type pipe line may be connected to the underground heat circulation pump 22. In this case, the upstream side (pump inflow side) and the downstream side (pump outflow side) of the geothermal circulation pump 22 are supplied with water sources (or constant temperature water) such as the aforementioned lakes, reservoirs, rivers, seas, hot springs, and wells, respectively. It may be connected to a chilled water supply), and the water from the water source or the like is directly pumped by the geothermal circulation pump 22 and used. That is, water such as the water source is supplied to the underground heat circulation pump 22 through a pipe line (upstream pipe line) connected to the pump upstream side, and a pipe line (downstream pipe line) connected to the pump downstream side. ), And is then guided to the underground heat source heat exchanger 45 provided in the downstream pipe line to exchange heat with the first refrigerant C1, and further through the downstream pipe line, the water source. And so on. In this case, the water source and the like connected to the upstream pipeline and the water source and the like connected to the downstream pipeline may be the same or different.

  Further, for example, in the above-described embodiment, a case where only one underground heat exchanger 23 is provided in the ground is described as an example, but the present invention is not limited to this, and a plurality of underground heat exchangers 23 are provided in the underground. It may be done. In that case, the plurality of underground heat exchangers 23 may be connected in parallel to each other or may be connected in series.

  Moreover, in the said embodiment, the case where this invention is applied to the composite heat source type heat pump apparatus provided with the geothermal heat pump circuit 40 using underground heat, and the air heat heat pump circuit 50 using air heat | fever one by one However, the present invention is not limited to this. That is, the present invention may be applied to a composite heat source type heat pump apparatus including the underground heat pump circuit 40 and the air heat pump circuit 50 and including three or more heat pump circuits. In this case, only the compressor of one heat pump circuit may be used as the main power source, and the compressors of other heat pump circuits may be used as the auxiliary power source.

  Furthermore, although the said embodiment demonstrated as an example the case where one or two heat exchange terminals 36 were connected as an indoor terminal, it is not restricted to this. That is, a configuration in which three or more indoor terminals are connected may be used.

1 heat pump device 20 underground heat circulation circuit (first heat pump circuit)
21 Underground heat pipe (heat medium pipe)
22 Geothermal circulation pump 23 Geothermal heat exchanger (heat source)
30 Terminal circulation circuit (load side circuit)
31 Load piping (circulating fluid piping)
32 Circulating fluid circulation pump (load-side circulation pump)
34 Return chilled water temperature sensor (circulating fluid temperature detection means)
36 Heat exchange terminal (load terminal)
40 Geothermal heat pump circuit (first heat pump circuit)
41 1st heat exchanger (1st load side heat exchanger)
42 1st refrigerant | coolant piping 42a 1st refrigerant | coolant discharge temperature sensor 42b 1st refrigerant | coolant temperature sensor (refrigerant temperature detection means)
43 1st compressor 44 1st expansion valve 45 Underground heat source heat exchanger (1st heat source side heat exchanger)
50 Air-heat heat pump circuit (second heat pump circuit)
51 2nd heat exchanger (2nd load side heat exchanger)
52 2nd refrigerant | coolant piping 52a 2nd refrigerant | coolant discharge temperature sensor 53 2nd compressor 54 2nd expansion valve 55 Air heat source heat exchanger (2nd heat source side heat exchanger)
57 Outside air temperature sensor (outside air temperature detection means)
61 Geothermal control device 61A Compressor control unit 61B Expansion valve control unit 61C Pump control unit 61p Switching control unit (control means)
62 air heat control device 62A compressor control unit 62B expansion valve control unit 62C fan control unit 62p switching control unit (control means)
C1 First refrigerant C2 Second refrigerant H1 Heat medium L Circulating fluid

Claims (6)

The first compressor, the first load side heat exchanger, and the first heat source side heat exchanger are connected by a first refrigerant pipe, and the first heat source side heat exchanger and the predetermined heat source are connected by a heat medium pipe. Connect to form a first heat pump circuit;
A second compressor, a second load side heat exchanger, and a second heat source side heat exchanger capable of exchanging heat with the outside air are connected by a second refrigerant pipe to form a second heat pump circuit;
The first load side heat exchanger, the second load side heat exchanger, and at least one load terminal are arranged in series on the upstream side of the second load side heat exchanger. Connected with the circulating fluid piping while forming the load side circuit,
A control means for switching which of the first compressor and the second compressor is a main power source and which is an auxiliary power source during operation;
Have a, in the composite source heat pump apparatus which performs heating operation by the load terminal,
In the load side circuit, a circulating fluid temperature detecting means for detecting a circulating fluid temperature flowing into the load side heat exchanger ;
Outside temperature detecting means for detecting outside temperature;
Provided,
The control means includes
During the operation, the outside air temperature detected by the outside air temperature detecting means is lower than a predetermined reference temperature in a state where the second compressor is a main power source and the first compressor is an auxiliary power source. Switching to a state where the first compressor is a main power source and the second compressor is an auxiliary power source, and
The circulating liquid by the circulating fluid temperature by the first compressor immediately before toggle its to the state of the main power Toshikatsu Minamoto the second compressor and the auxiliary power source and the circulating fluid temperature detecting means detects drops If the deviation between the temperature and the target temperature of the circulating fluid exceeds a predetermined threshold value, the maximum rotational speed of the compressor rotation speed of the first compressor became the main power source to the switching and simultaneous composite source heat pump apparatus characterized by increasing the. The control means includes
When the state determined to require switching between the compressor serving as the main power source and the compressor serving as the auxiliary power source continues for a predetermined period, and the first compressor as the main power source if the difference is equal to or greater than the threshold value by immediately before switching to the state in which the second compressor and the auxiliary power source, the circulating fluid temperature, wherein the circulating fluid temperature detecting unit detects is decreased, the switching composite heat source heat pump apparatus according to claim 1, wherein the rotational speed of the same time becomes the main power source of the first compressor, characterized in that to increase the maximum rotational speed of the compressor. The load side circuit is:
Connecting a plurality of the load terminals, the first load-side heat exchanger, the second load-side heat exchanger,
The control means includes
When the state determined to require switching between the compressor serving as the main power source and the compressor serving as the auxiliary power source continues for a predetermined period, and the first compressor as the main power source Immediately before switching to the state where the second compressor is used as an auxiliary power source, the deviation is caused by the decrease in the circulating fluid temperature detected by the circulating fluid temperature detecting means due to an increase in the number of load terminals to be operated. if equal to or more than the threshold value, according to claim 1, characterized in that to increase the rotational speed of the became switched simultaneously the main power source of the first compressor to the maximum rotational speed of the compressor or The composite heat source heat pump apparatus according to claim 2 . The first compressor, the first load side heat exchanger, and the first heat source side heat exchanger are connected by a first refrigerant pipe, and the first heat source side heat exchanger and the predetermined heat source are connected by a heat medium pipe. Connect to form a first heat pump circuit;
A second compressor, a second load side heat exchanger, and a second heat source side heat exchanger capable of exchanging heat with the outside air are connected by a second refrigerant pipe to form a second heat pump circuit;
The first load side heat exchanger, the second load side heat exchanger, and at least one load terminal are arranged in series on the upstream side of the second load side heat exchanger. Connected with the circulating fluid piping while forming the load side circuit,
A control means for switching which of the first compressor and the second compressor is a main power source and which is an auxiliary power source during operation;
In a composite heat source heat pump device that performs cooling operation by the load terminal,
In the load side circuit, a circulating fluid temperature detecting means for detecting a circulating fluid temperature flowing into the load side heat exchanger;
Outside temperature detecting means for detecting outside temperature;
Provided,
The control means includes
During the operation, the outside air temperature detected by the outside air temperature detecting means becomes higher than a predetermined reference temperature in a state where the second compressor is used as a main power source and the first compressor is used as an auxiliary power source. Switching to a state where the first compressor is a main power source and the second compressor is an auxiliary power source, and
Immediately before switching to the state where the first compressor is used as a main power source and the second compressor is used as an auxiliary power source, and the circulating fluid temperature detected by the circulating fluid temperature detecting means is increased, the circulating fluid temperature is increased. And the target circulating fluid temperature exceed a predetermined threshold value, the rotational speed of the first compressor that is the main power source is increased to the maximum rotational speed of the compressor simultaneously with the switching. Make
A composite heat source heat pump device characterized by that. The control means includes
When the state determined to require switching between the compressor serving as the main power source and the compressor serving as the auxiliary power source continues for a predetermined period, and the first compressor as the main power source Immediately before switching to the state where the second compressor is used as an auxiliary power source, the switching is performed when the deviation exceeds the threshold value due to the circulating fluid temperature detected by the circulating fluid temperature detecting means rising. At the same time, the rotational speed of the first compressor that is the main power source is increased to the maximum rotational speed of the compressor.
The combined heat source heat pump apparatus according to claim 4, wherein The load side circuit is:
Connecting a plurality of the load terminals, the first load-side heat exchanger, the second load-side heat exchanger,
The control means includes
When the state determined to require switching between the compressor serving as the main power source and the compressor serving as the auxiliary power source continues for a predetermined period, and the first compressor as the main power source Immediately before switching to the state where the second compressor is used as an auxiliary power source, the deviation is caused by an increase in the circulating fluid temperature detected by the circulating fluid temperature detecting means due to an increase in the number of load terminals to be operated. When the threshold value is exceeded, the rotational speed of the first compressor that has become the main power source at the same time as the switching is increased to the maximum rotational speed of the compressor.
The composite heat source heat pump device according to claim 4 or 5, wherein

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