KR102014931B1 - Hybrid outdoor air cooling system using natural energy and control method thereof - Google Patents

Abstract

The present invention relates to a hybrid outside air cooling system using natural energy, and a control method thereof. The purpose of the present invention is to have a precooling method using outside air as a cooling heat source, and to avoid damage caused by frequent on / off of the compressor, that is, the estrus operation of the compressor. The present invention provides a hybrid outdoor air cooling system using natural energy and a control method thereof to prevent the damage. The present invention for this purpose is an evaporator for inducing heat exchange between the supply air and the refrigerant supplied to the computer center; A first refrigeration system and a second refrigeration system configured to share the evaporator; Cooling tower; A cooling water coil disposed in front of the evaporator; A cooling water circulation pipe installed to connect the cooling tower, the cooling water coil, and the first and second condensers; A first bypass pipe installed in the cooling water circulation pipe; A first control valve installed at a connection point between the first bypass pipe and the cooling water circulation pipe; Air supply temperature sensor; Ventilation temperature sensor; Coolant temperature sensor; A second bypass pipe connecting the coolant supply line and the coolant return line; A second control valve installed at a connection point between the cooling water circulation pipe and the second bypass pipe; And controlling the first control valve in response to a result of comparing the detected air supply temperature with a preset air supply temperature set value, and a result of comparing the detected coolant temperature with a preset coolant temperature upper limit value and a lower limit value. If the detected ventilation temperature is equal to or greater than the preset ventilation temperature setting value, the air supply temperature is higher than the air supply temperature setting value by comparing the air supply temperature with the air supply temperature setting value after the operation of the first compressor. A controller having a function of additionally operating a second compressor, and controlling a flow rate of the cooling water supplied to the first and second condensers by controlling the second control valve in response to the condensing pressure of the first condenser and the second condenser; It provides a hybrid outdoor air-conditioning system using the natural energy, and a control method thereof comprising.

Description

Hybrid outdoor air cooling system using natural energy and control method

The present invention relates to a cooling system for maintaining the temperature of a computer center at a set level, and more particularly, in the summer, the cooling water from the cooling tower is used to condense the high-temperature, high-pressure refrigerant discharged from the compressor, and in the winter, the cooling water is directly cooled. It is used as a heat source, and the cooling season is used as a primary cooling heat source in the transition season to compensate for the insufficient cooling load by operating the compressor, but it prevents the estrus operation of the compressor, and the condenser pressure of the condenser is lowered due to the cooling of the cooling water It includes the function to prevent abnormal operation of the compressor, and the function of stabilizing the temperature of the air supply supplied to the computer center to a certain level, and using the natural energy made to enable rapid conversion of air cooling and cooling using the refrigeration system Hybrid air conditioning system and its components It relates to a method.

Due to the development of information technology, the cooling load per unit area of computer center is rapidly increasing, and the pre-cooling system using natural energy is developed to reduce the cooling energy of computer center that needs cooling even in winter due to internal heating equipment such as server. It is used.

 On the other hand, the conventional precooling system is divided into a direct cooling method for cooling by using the outside air directly, and an indirect cooling method using the cooling heat of the outside air using a heat exchanger or the like.

The direct cooling type precooling system is excellent in energy saving efficiency by using outdoor air directly as a cooling heat source, but it has not been recently adopted due to difficulties in indoor inflow and humidity management of external pollutants.

The indirect cooling type precooling system is divided into air-air heat exchange method and air-water heat exchange method, and the double air-air heat exchange method has a very small specific heat of air, so that the size of the air duct and air conditioning equipment is very large. There are disadvantages.

Air-water heat exchange, on the other hand, is an advanced precooling system that can overcome these drawbacks.

However, in order to increase energy efficiency, combined cooling operation that operates both air cooling and compressor cooling at the same time is inevitable, and due to difficulty in control method, air cooling efficiency decreases due to incorrect operation, and in the worst case, frequent compressor failure occurs. There is a problem.

Patent Application Publication No. 10-0933515 (August 23, 2009)

The present invention has been made in consideration of the above problems, and an object of the present invention is to have a precooling method using outside air as a cooling heat source, to prevent damage caused by frequent on-off of the compressor, that is, the estrus operation of the compressor. A hybrid outdoor air cooling system using a natural energy and a control method thereof are provided.

Another object of the present invention is to provide a hybrid outside air cooling system using natural energy and a control method thereof that can be quickly converted to a general cooling operation system using a refrigeration system in the course of operating the cooling system as a natural cooling operation system.

Still another object of the present invention is to provide a hybrid outside air cooling system using natural energy that can prevent abnormal operation of a compressor generated due to the temperature of the cooling water being too low, and a control method thereof.

Still another object of the present invention is to provide a hybrid outdoor air cooling system using natural energy and a control method thereof using natural energy capable of maintaining a constant air supply temperature supplied to a computer center.

The present invention to achieve the object as described above and to perform the problem for eliminating the conventional defects is an evaporator for inducing the cooling of the air supply through heat exchange between the supply air and the refrigerant supplied to the computer center; A first refrigeration system constituted by a first compressor, a first condenser, a first expansion valve, and the evaporator; A second refrigeration system constituted by a second compressor, a second condenser, a second expansion valve and the evaporator; A cooling tower configured to heat-exchange the cooling water used for condensation of the refrigerant in the first condenser and the second condenser with outside air; A cooling water coil disposed in front of the evaporator so as to face the air supply before the evaporator to cool the air supply through heat exchange between the cooling water and the air supply; A cooling water circulation pipe installed to connect the cooling tower, the cooling water coil, and the first and second condensers to circulate the cooling water; A first bypass pipe installed in the cooling water circulation pipe so that the cooling water flowing through the cooling water circulation pipe can flow without passing through the cooling water coil; A first control valve installed at a connection point between the first bypass pipe and the cooling water circulation pipe to control the flow of the cooling water; An air supply temperature sensor detecting a temperature of an air supply supplied to the computer center; A ventilation temperature sensor detecting a temperature of ventilation discharged from the computer center; A coolant temperature sensor installed at the coolant circulation pipe to detect a temperature of the coolant; A second bypass pipe connecting the cooling water supply line and the cooling water return line constituting the cooling water circulation pipe; A second control valve installed at a connection point between the cooling water circulation pipe and the second bypass pipe to control the flow of the cooling water; And controlling the first control valve in response to a result of comparing the detected air supply temperature with a preset air supply temperature set value, and a result of comparing the detected coolant temperature with a predetermined coolant temperature upper limit value TW1 and a lower limit value TW2. When the ventilation temperature detected by the ventilation temperature sensor is equal to or greater than a preset ventilation temperature setting value, the air supply temperature is supplied through the function of operating the first compressor and comparing the air supply temperature with the air supply temperature setting value after the first compressor is operated. When the temperature is higher than the set value, the function of additionally operating the second compressor, and controls the second control valve in response to the condensing pressure of the first condenser and the second condenser to adjust the flow rate of the cooling water supplied to the first and second condensers It provides a hybrid outdoor air-conditioning system using natural energy, including a controller having a function.

delete

In the hybrid outdoor air cooling system using the natural energy, a third bypass pipe for supplying a portion of the high-temperature, high-pressure refrigerant gas discharged from the first compressor to the rear end of the first expansion valve; A first displacement regulating valve installed in the third bypass pipe to control a flow rate of the refrigerant gas bypassed while controlling a flow path of the third bypass pipe; A fourth bypass pipe configured to supply a portion of the high-temperature, high-pressure refrigerant gas discharged from the second compressor to the rear end of the second expansion side; And a second capacity control valve installed in the fourth bypass pipe to control a flow rate of the refrigerant gas being bypassed while controlling the flow path of the fourth bypass pipe. The controller further includes a preset air supply temperature detected by the controller. When the capacity control valve is lower than the operating temperature value, the first capacity control valve and the second capacity control valve may be opened to supply coolant gas having a high temperature and high pressure to the rear end of the first and second expansion valves to increase the air supply temperature. have.

In another aspect, the present invention is to control the hybrid outside air cooling system using the natural energy, setting the air supply temperature set value, the ventilation temperature set value, the coolant temperature upper limit value, the coolant temperature lower limit value, the capacity control valve operating temperature value (S10); Comparing the air supply temperature detected by the air supply temperature sensor with the air supply temperature setting value and determining whether the detected air supply temperature is smaller than the air supply temperature setting value (S20); If the air supply temperature is smaller than the air supply temperature set value, controlling the first control valve to open the first bypass pipe 100%, stopping the first and second refrigeration systems, and performing a blowing operation (S30); If the air supply temperature is not smaller than the air supply temperature set value, comparing the coolant temperature detected by the coolant temperature sensor with the upper limit of the coolant temperature to determine whether the coolant temperature is greater than the upper limit (S40); As a result of the determination in step S40, if the coolant temperature is greater than the upper limit value, the first control valve is controlled to open 100% of the first bypass pipe, and the general cooling operation is performed to cool the air supply by operating the first and second refrigeration systems. Step (S50); Determining whether the coolant temperature is greater than the coolant temperature lower limit if the coolant temperature is not greater than the upper limit (S60); If the coolant temperature is greater than the lower limit as a result of the determination in step S60, the first control valve is controlled to close the first bypass pipe 100% so that the coolant supplied from the cooling tower cools the air supply while passing through the coolant coil. Performing a combined cooling operation for cooling the air supply through the operation of the first and second refrigeration systems (S70); And if the coolant temperature is not greater than the lower limit as a result of the determination at step S60, by controlling the first control valve to partially close the first bypass pipe according to the air supply temperature, the coolant supplied from the cooling tower passes through the coolant coil to cool the air supply. And a step of performing a natural cooling operation by stopping the first and second refrigeration systems (S80). It provides a control method of a hybrid outside air cooling system using natural energy.

Meanwhile, in the control method of the hybrid outside air cooling system using the natural energy, steps S50 and S70 may include determining whether a ventilation temperature detected by the ventilation temperature sensor is greater than a ventilation temperature set value (S91); As a result of the determination in step S91, when the ventilation temperature is greater than the ventilation temperature set value, cooling the air supply by operating the first refrigeration system through operation of the first compressor (S92); After the step S92, determining whether the air supply temperature detected by the air supply temperature sensor is greater than the air supply temperature set value (S93); As a result of the determination in step S93, if the air supply temperature is greater than the air supply temperature set value, additionally starting the second refrigeration system through the operation of the second compressor, and repeating the process again from the step S93 (S94); And when the air supply temperature is smaller than the air supply temperature set value as a result of the determination in step S93, repeating the process from step S91 again (S95). The first and second refrigeration systems may be sequentially operated.

On the other hand, in the control method of the hybrid outside air cooling system using the natural energy, during operation of the first compressor for the operation of the first refrigeration system, the air supply temperature detected by the air supply temperature sensor and the capacity control valve operating temperature value If the air supply temperature is less than the capacity control valve operating temperature value step of supplying a high-temperature, high-pressure refrigerant gas discharged from the first compressor through the opening of the first capacity control valve to the rear end of the first expansion valve to increase the temperature of the air supply (S101) ); And comparing the air supply temperature detected by the air supply temperature sensor with the capacity control valve operating temperature value during operation of the second compressor for operating the second refrigeration system, and if the air supply temperature is smaller than the capacity control valve operating temperature value, the second capacity. Supplying a high-temperature, high-pressure refrigerant gas discharged from the second compressor through the opening of the control valve to the rear end of the second expansion valve to increase the temperature of the air supply (S102); may be further included.

Meanwhile, in the control method of the hybrid outside air cooling system using the natural energy, the cooling water flowing through the cooling water circulation pipe is always passed through the first and second condensers during the natural cooling operation through the step S80. When the refrigeration system or the second refrigeration system is operated, the condensation environment of the refrigerant is rapidly generated, thereby shortening the arrival time of normal operation of the first and second refrigeration systems.

Meanwhile, in the control method of the hybrid outside air cooling system using the natural energy, the second bypass pipe is partially closed according to the condensation pressure of the first condenser or the second condenser during the complex cooling operation according to the step S70. Controlling the control valve to adjust the flow rate of the cooling water supplied to the first and second condensers (S111); may be further included.

According to the present invention having the characteristics as described above, by using the outdoor air season or the cold outside air temperature of the outside air as the cooling heat source, it is possible to reduce the energy required for cooling the computer center.

In addition, the first compressor of the first refrigeration system that cools the air supply in advance during the normal cooling operation or the combined cooling operation is controlled based on the ventilation temperature, and the second compressor of the second refrigeration system that operates later is based on the air supply temperature. The first compressor is controlled based on the ventilation temperature at the beginning of the operation of the computer center where the variation of the cooling load is large, thereby cooling the computer center and thus preventing damage due to the estrus operation of the compressor. It works.

In addition, when the cooling system is operated as a natural cooling operation system using the outdoor air, switching to a general cooling operation system or a complex cooling operation system using a refrigerating system has an effect of shortening the arrival time of the normal operation of the refrigeration system.

In addition, by applying a control method according to the condenser refrigerant pressure there is an effect that can prevent the abnormal operation of the compressor due to the supply of the coolant of too low temperature to the condenser of the refrigeration system in the change of temperature of the outside air.

In addition, when the air supply temperature is lower than the set temperature, by supplying a high-temperature high-pressure refrigerant discharged from the compressor to the evaporator side to prevent the air supply temperature is lowered below the set temperature it can be maintained at a constant level. By preventing a sudden drop in the air supply temperature has the effect of preventing condensation on the server of the computer center.

1 is a structural diagram of a hybrid outside air cooling system according to a preferred embodiment of the present invention,
2 is a flowchart illustrating a control method of a hybrid outside air cooling system according to a preferred embodiment of the present invention;
Figure 3 is a structural diagram showing the summer operating state of the hybrid outside air cooling system according to a preferred embodiment of the present invention,
Figure 4 is a structural diagram showing the operating state of the season change of the hybrid outside air cooling system according to a preferred embodiment of the present invention,
Figure 5 is a structural diagram showing a winter operating state of the hybrid outside air conditioning system according to a preferred embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In describing the present invention, if it is determined that the detailed description of the related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

1 is a structural diagram of a hybrid outside air cooling system according to a preferred embodiment of the present invention.

The hybrid outdoor air cooling system using natural energy according to the present invention can reduce the energy required for cooling the air supply by using outdoor air as a cooling heat source when cooling of the air supply using outdoor air is possible, and two refrigeration systems Including, but one of the refrigeration system is to control the cooling temperature based on the ventilation temperature when the initial cooling load of the computer center operating at low load, the other refrigeration system is the air supply temperature after the stabilization of the computerization center to some extent Controlled by the reference to perform the cooling has a feature to prevent the estrous operation of the compressor provided in the refrigeration system.

For reference, the load characteristics of the computer center are maintained around 20% at the initial stage after completion, and about 90% of the servers are installed and operated when the computer center is stabilized after a certain period. In addition, since the computer center is installed inside the building and there is no inflow of outside air and sunlight, the cooling load of the air conditioning system is mostly installed server capacity, and the operation measures for initial low load operation are necessary according to the server installation. When completed, there is a characteristic that there is no change in cooling load.

In consideration of the characteristics of the computer center as described above, the present invention maintains a constant air supply temperature even during low load operation, and the refrigeration temperature of any one of two refrigeration systems at the initial operation of the computer center to prevent the compressor estrus operation. It is to be controlled based on the to prevent frequent on-off of the compressor.

On the other hand, the two refrigeration systems assume that the indoor load of the computer center is 100%, and if the indoor load is less than 50%, the compressor controlled based on the ventilation temperature is operated to cool and the indoor load is 50% or more. In this case, the compressor of the other refrigeration system is operated while being controlled based on the air supply temperature.

Such a hybrid outdoor air cooling system according to the present invention is the evaporator 110, the first refrigeration system 120, the second refrigeration system 130, the cooling tower 140, the cooling water coil 150, the cooling water circulation pipe 160, It comprises a first bypass pipe 170, the first control valve 180, the air supply temperature sensor 190, the ventilation temperature sensor 200, the coolant temperature sensor 210, the controller 220.

The evaporator 110 is configured to induce cooling of the air supply through heat exchange between the air supply and the refrigerant supplied to the computer center (S).

The evaporator 110 is provided with a first coil 111 through which the refrigerant supplied from the first refrigeration system 120 is circulated and a second coil 112 through which the refrigerant supplied from the second refrigeration system 130 is circulated. .

The first refrigeration system 120 includes a first compressor 121 for compressing the refrigerant evaporated while passing through the first coil 111, and a first condenser for condensing the refrigerant compressed by the first compressor 121. And a first expansion side 123 for lowering the pressure of the refrigerant condensed in the first condenser 122 and the evaporator 110.

The second refrigeration system 130 includes a second compressor 131 for compressing a refrigerant evaporated while passing through the second coil 112, and a second condenser for condensing the refrigerant compressed by the second compressor 131. 132, a second expansion side 133 for lowering the pressure of the refrigerant condensed in the second condenser 132, and the evaporator 110.

As a result, the first refrigeration system 120 and the second refrigeration system 130 share one evaporator 110, but are configured to independently supply a refrigerant.

The cooling tower 140 is connected to the first condenser 122 and the second condenser 132 and is configured to supply cooling water to the first condenser 122 and the second condenser 132.

The cooling water coil 150 cools the air supply by using the cooling water cooled by the outside air, and is disposed in front of the evaporator 110 so as to face the air supply before the evaporator 110, and from the cooling tower 140. The cooling water supplied to the two condensers 122 and 132 is configured to exchange heat with the supply air.

The cooling water circulation pipe 160 is installed to connect the cooling tower 140, the cooling water coil 150, and the first and second condensers 122 and 132 so that the cooling water discharged from the cooling tower 140 is the cooling water coil 150 and the first, It is configured to return to the cooling tower 140 through the two condensers (122,132).

The first bypass pipe 170 is a pipe that allows the cooling water discharged from the cooling tower 140 to flow through the cooling water coil 150 without passing through the cooling water coil 150, and the front end of the cooling water coil 150. Is branched from the cooling water circulation pipe 160 in the rear end of the cooling water coil 150 is installed to have a structure that is connected to the cooling water circulation pipe 160 again.

The first control valve 180 controls the flow path so that the cooling water discharged from the cooling tower 140 can selectively pass through the cooling water coil 150, and the first bypass pipe 170 and the cooling water circulation pipe 160 It is installed at the connection point of).

The first control valve 180 opens 100% of the flow path of the first bypass pipe 170 or opens the flow path of the first bypass pipe 170 in response to the control signal generated by the controller 220. The cooling water is distributed to the cooling water coil 150 and the first bypass pipe 170 at a predetermined ratio by closing the% or partially closing the flow path of the first bypass pipe 170 in proportion to the air supply temperature.

The air supply temperature sensor 190 is configured to detect the temperature of the air supply is passed through the evaporator 110 to the computer center (S).

The ventilation temperature sensor 200 is configured to detect the temperature of the ventilation discharged from the computer center (S).

The cooling water temperature sensor 210 is installed in the cooling water circulation pipe 160 to detect the temperature of the cooling water from the cooling tower 140.

The controller 220 controls the hybrid outside air cooling system according to the present invention according to a pre-input program.

Meanwhile, the controller 220 according to a preferred embodiment of the present invention has a function of comparing the air supply temperature detected by the air supply temperature sensor 190 with a preset air supply temperature set value, and the coolant temperature detected by the coolant temperature sensor 210. A function of comparing a preset coolant temperature upper limit value and a lower limit value; controlling the first control valve 180 according to the comparison result; and, if the ventilation temperature detected by the ventilation temperature sensor 200 is equal to or greater than a preset ventilation temperature set value. The second compressor 131 is additionally operated when the air supply temperature is higher than the air supply temperature setting value through the function of operating the first compressor 121 and comparing the air supply temperature and the air supply temperature setting value after the operation of the first compressor 121. It has a function to make.

That is, the controller 220 receives and stores the temperature values detected by the air supply temperature sensor 190, the ventilation temperature sensor 200, and the coolant temperature sensor 210, and sets the air supply temperature set value and the ventilation temperature from an administrator or a user. The set value and the coolant temperature set value are received and stored, and the related equipment is controlled to achieve cooling according to the situation by comparing the detected temperature value with the set value.

In the hybrid outside air cooling system configured as described above, the first and second condensers 122 and 132 and the first and second compressors 121 and 131 can function normally even when the temperature of the cooling water is too low. The second bypass pipe 230 and the second control valve 240 for adjusting the flow rate of the condensate supplied to may be further included.

The second bypass pipe 230 is configured to connect the coolant supply line 161 and the coolant return line 162 constituting the coolant circulation pipe 160 to each other, and the second bypass pipe 230 is a cooling tower. It is configured to connect the coolant supply line 161 and the coolant return line 162 in the section between the 140 and the first and second condensers 122 and 132.

The second control valve 240 is installed at a connection point between the second bypass pipe 230 and the coolant return line 162 and is configured to control a flow path corresponding to a signal generated from the controller 220.

More specifically, the second control valve 240 opens 100% of the flow path of the second bypass pipe 230 or the second bypass pipe 230 in response to a control signal generated from the controller 220. It is configured to close the flow path of 100% or partially close the flow path of the second bypass pipe 230 to supply only a part of the cooling water to the first and second condensers (122,132).

When the second bypass pipe 230 and the second control valve 240 are further included, the controller 220 corresponds to the condensation pressure of the first and second condensers 122 and 132. It further includes a function to adjust the flow rate of the cooling water supplied to the first and second condensers (122,132).

That is, the controller 220 receives the condensation pressure of the first condenser 122 and the second condenser 132 from the pressure sensors installed in the first condenser 122 and the second condenser 132, and is a manager or a user. When the condensation pressure is lower than the condensation pressure setting value by comparing the condensing pressure setting value previously input by the detected condensing pressure setting value, all or part of the cooling water supplied to the first and second condensers 122 and 132 is the second bypass tube The second control valve 240 is controlled to be returned to the cooling tower 140 as it is through the 230.

For reference, the lower the temperature of the cooling water supplied to the condenser, the smoother the condensation of the refrigerant can be induced. However, if the temperature of the cooling water is below a certain level, the condensation pressure is lowered and the temperature of the refrigerant evaporation pressure is lowered due to the characteristic of the refrigerant compressor. It may be difficult to adjust and eventually develop into a failure of the compressor, but the coolant having a temperature that is too low by using the second bypass pipe 230 and the second control valve 240 as described above may be the first and second condensers 122 and 132. By appropriately controlling the supply to the low temperature it is possible to prevent the failure of the compressor due to the coolant.

In addition, the controller 220 allows all of the cooling water via the cooling water coil 150 to be supplied to the first and second condensers 122 and 132 during the winter season in which 100% natural cooling operation is possible through cooling of the air supply using the cooling water. By allowing the first and second refrigeration systems 120 and 130 to maintain the low temperature state, the first and second refrigeration systems 120 and 130 may further include a function to shorten the normal operation arrival time of the refrigeration cycle.

Meanwhile, the third bypass pipe 250, the first capacity control valve 260, the fourth bypass pipe 270, and the second capacity control valve 280 may be further included to stabilize the air supply temperature.

The third bypass pipe 250 supplies a portion of the refrigerant gas discharged from the first compressor 121 to the rear end of the first expansion side 123 by bypassing the first condenser 122 and the first expansion side 123. And to form a flow path that causes it to flow.

The first displacement control valve 260 is installed in the third bypass pipe 250 and configured to control the flow path of the third bypass pipe 250.

The fourth bypass pipe 270 supplies a portion of the refrigerant gas discharged from the second compressor 131 to the rear end of the second expansion side 133 by bypassing the second condenser 132 and the second expansion side 133. And to form a flow path that causes it to flow.

The second displacement control valve 280 is installed in the fourth bypass pipe 270 and configured to control the flow path of the fourth bypass pipe 270.

When the third and fourth bypass pipes 250 and 270 and the first and second capacity control valves 260 and 280 are further included, the controller 220 detects that the detected air supply temperature is lower than the capacity control valve operating temperature value TC. In this case, the first capacity control valve 260 and the second capacity control valve 280 are opened to supply a high-temperature, high-pressure refrigerant gas to the rear ends of the first and second expansion valves 123 and 133 to further increase the air supply temperature. .

In the drawings, reference numeral 290 denotes a pump, 300 a blower, 310 a filter drier, 320 a sight glass, 330 a refrigerant liquid solenoid valve, 340 a refrigerant gas solenoid valve, and 350 a suction strainer.

Figure 2 is a flow chart for a control method of a hybrid outside air conditioning system according to a preferred embodiment of the present invention, Figure 3 is a structural diagram showing the summer operating state of the hybrid outside air conditioning system according to a preferred embodiment of the present invention, Figure 4 5 is a structural diagram showing the operating state of the hybrid outdoor air conditioning system according to the preferred embodiment of the present invention, Figure 5 shows a structural diagram showing the operating state of the hybrid outdoor air conditioning system according to the preferred embodiment of the present invention.

The control method according to the present invention implemented by the hybrid outside air cooling system configured as described above is the air supply temperature set value (TA1), ventilation temperature set value (TA2), coolant temperature upper limit value (TW1), coolant temperature lower limit value (TW2), capacity Setting a control valve operating temperature value TC (S10); Comparing the air supply temperature detected by the air supply temperature sensor 190 with the air supply temperature set value TA1 to determine whether the detected air supply temperature is smaller than the air supply temperature set value TA1 (S20); When the air supply temperature is smaller than the air supply temperature set value TA1, the first control valve 180 is controlled to open the first bypass pipe 170 at 100%, and the first and second refrigeration systems 120 and 130 are stopped. Performing a blowing operation (S30); When the air supply temperature is not smaller than the air supply temperature set value TA1, the coolant temperature detected by the coolant temperature sensor 210 and the coolant temperature upper limit value TW1 are compared to determine whether the coolant temperature is greater than the coolant temperature upper limit value TW1. Step S40; When the coolant temperature is greater than the coolant temperature upper limit value TW1 as a result of the determination in step S40, the first control valve 180 is controlled to open the first bypass pipe 170 at 100%, and the first and second refrigeration systems 120 and 130 are used. Performing a general cooling operation for cooling the air supply through the operation of the step (S50); Determining whether the coolant temperature is greater than the coolant temperature lower limit value TW2 when the coolant temperature is not greater than the coolant temperature upper limit value TW1 (S60); If the coolant temperature is greater than the coolant temperature lower limit value TW2 as a result of the determination in step S60, the coolant supplied from the cooling tower 140 is controlled by controlling the first control valve 180 to close the first bypass pipe 170 at 100%. Cooling the air supply while passing through the cooling water coil 150, and performing a combined cooling operation for cooling the air supply through the operation of the first and second refrigeration systems (120, 130) (S70); And when the coolant temperature is not greater than the coolant temperature lower limit value TW2 as a result of the determination at step S60, the first control valve 180 is controlled to partially close the cooling tower 140 according to the air supply temperature. Cooling water supplied from the cooling water coil 150 through the cooling water coil 150, and stopping the first and second refrigeration system (120,130) to perform a natural cooling operation (S80).

In step S10, the manager or the user may supply the air supply temperature set value TA1, the ventilation temperature set value TA2, the coolant temperature upper limit value TW1, the coolant temperature lower limit value TW2, the capacity control valve operating temperature value TC, and the condensation pressure. The setting value is input to the controller 220.

In step S20, the controller 220 compares the air supply temperature detected by the air supply temperature sensor 190 with the air supply temperature set value TA1 to determine whether the detected air supply temperature is smaller than the air supply temperature set value TA1. You lose.

The step S30 is performed when the air supply temperature is smaller than the air supply temperature set value TA1 as a result of the determination of step S20. The air supply temperature is already lower than the air supply temperature set value TA1 required for cooling the computer center. Therefore, cooling using the natural cooling system or the refrigeration system using the outside air is not required.

Therefore, in step S30, the controller 220 controls the first control valve 180 to open the first bypass pipe 170 at 100%, so that the coolant does not pass through the coolant coil 150 and the first bypass pipe 170. By bypassing) and by stopping or maintaining the first and second refrigeration systems (120,130), it is made to operate the hybrid outdoor air conditioning system as a blowing operation system.

The step S40 is performed when the air supply temperature is not smaller than the air supply temperature set value TA1 as a result of the determination in step S20. The controller 220 detects the coolant temperature and the coolant temperature upper limit value (the coolant temperature detected by the coolant temperature sensor 210). TW1) is compared to determine whether the coolant temperature is larger than the coolant temperature upper limit value TW1.

The step S50 is performed when the coolant temperature is greater than the coolant temperature upper limit value TW1 as a result of the determination in step S40. The controller 220 controls the first control valve 100 to open the first bypass pipe 170 at 100%. 180 to control the cooling water to bypass through the first bypass pipe 170 without passing through the cooling water coil 150, and by operating the first and second refrigeration systems (120, 130), thereby cooling the hybrid outside air cooling system in general It is made by operating with a driving system.

The step S50 is a step performed at a time when the temperature of the outside air is high, such as in the summer, and cooling of the air supply using the high temperature cooling water is impossible, so that the cooling water coil is 100% open through the first bypass pipe 170. To bypass 150, the air supply is cooled by supplying a refrigerant to the evaporator 110 by operating the first refrigeration system 120 and the second refrigeration system 130.

The step S60 is performed when the coolant temperature is not greater than the coolant temperature upper limit value TW1 as a result of the determination of step S40. The controller 220 determines whether the coolant temperature is greater than the coolant temperature lower limit value TW2. .

The step S70 is a step performed when the coolant temperature is greater than the coolant temperature lower limit value TW2 as a result of the determination of step S60, that is, when the coolant temperature is smaller than the coolant temperature upper limit value TW1 and larger than the coolant temperature lower limit value TW2. The control unit 180 controls the first control valve 180 to close the first bypass pipe 170 by 100% to cool the air supply while passing the cooling water coil 150 through the cooling water coil 150. Together with the operation of the first and second refrigeration systems (120,130) to cool the air supply is made to operate the hybrid outdoor air conditioning system as a combined operation system.

The step S70 is performed in a season with a large change in temperature of the outside air, and the first control valve 180 controls the first control valve 180 to exchange heat with the supply air while the coolant water from the cooling tower 140 passes through the coolant coil 150. Closing the bypass pipe 170 by 100%, and through the proper operation of the first and second refrigeration system (120,130) will be made to compensate for the insufficient cooling load.

On the other hand, the first control valve 180 that operates to open and close the first bypass pipe 170 has an opening ratio of the flow path of the first bypass pipe 170 side and the coolant coil 150 side flow path corresponding to the temperature of the air supply. The temperature of the air supply may be controlled by adjusting the flow rate of the cooling water supplied to the cooling water coil 150.

On the other hand, the operation of the first and second refrigeration system (120,130) in the step S50 and S70 is the first and second refrigeration system (120,130) is sequentially operated through the following process.

More specifically, in the implementation of the steps S50 and S70, determining whether the ventilation temperature detected by the ventilation temperature sensor 200 is greater than the ventilation temperature set value TA2 (S91); As a result of the determination in step S91, when the ventilation temperature is greater than the ventilation temperature set value TA2, cooling the air supply by operating the first refrigeration system 120 through the operation of the first compressor 121 (S92); After the step S92, determining whether the air supply temperature detected by the air supply temperature sensor 190 is greater than the air supply temperature set value TA1 (S93); As a result of the determination in step S93, if the air supply temperature is greater than the air supply temperature set value TA1, the second refrigeration system 130 is additionally operated through the operation of the second compressor 131, and then repeated again from the step S93. Step S94; And if the air supply temperature is smaller than the air supply temperature set value TA1 as a result of the determination in step S93, repeating from step S91 again (S95).

During the initial low load operation of the computer center through the steps S91 to S95, the first compressor 121 of the first refrigeration system 120 is controlled while controlling the ventilation temperature, and the computer center is operated. When the situation is normalized and there is no danger of the estrus operation, the second refrigeration system 130 is controlled based on the air supply temperature, thereby supplementing the cooling load insufficient by the first refrigeration system 120 alone.

On the other hand, the ventilation temperature is changed slower than the air supply temperature, by controlling the first compressor 121 based on the ventilation temperature, the frequent on of the first compressor 121 at the initial stage of operation of the computer center, the fluctuation range of the cooling load is large It is possible to prevent the estrous operation due to the off.

In addition, during operation of the first refrigeration system 120 and the second refrigeration system 130, comparing the air supply temperature and the capacity control valve operating temperature value (TC) and according to the result of the high-temperature refrigerant gas evaporator 110 Supplying the front end to increase the temperature of the air supply may be further included (S101, S102).

More specifically, in step S101, during operation of the first compressor 121, the controller 220 compares the air supply temperature detected by the air supply temperature sensor 190 with a preset capacity control valve operating temperature value TC. If the temperature is smaller than the capacity control valve operating temperature value TC, the high temperature and high pressure refrigerant gas discharged from the first compressor 121 through the opening of the first capacity control valve 260 to the rear end of the first expansion valve 123. As the supply of the high-temperature, high-pressure refrigerant gas to the rear end of the first expansion valve 123, the temperature of the coolant supplied to the evaporator 110 increases, thereby increasing the temperature of the air supply.

In step S102, during operation of the second compressor 131, the controller 220 compares the air supply temperature detected by the air supply temperature sensor 190 with a preset capacity control valve operating temperature value TC to adjust the air supply temperature. When the valve operation temperature value TC is smaller than the valve operating temperature value TC, the refrigerant gas of the high temperature and high pressure discharged from the second compressor 131 is supplied to the rear end of the second expansion valve 133 through the opening of the second capacity control valve 280. This control makes it possible to increase the temperature of the air supply.

According to the step S101 and S102, it is possible to solve the problem that the supply air temperature falls below the set temperature due to a sudden drop in the outside temperature or abnormal operation of the refrigeration system.

That is, in the case of a computer center, it is very important to keep the temperature of the air supply constant. If the change in supply air temperature is large, problems due to expansion and contraction of precision parts may occur, and moisture may be caused by condensation inside the server when the air supply suddenly decreases in temperature, which may cause fatal defects.

Therefore, it is possible to build a high stability computer center cooling system by stabilizing the temperature of the air supply through the air supply temperature stabilization technology as described above.

On the other hand, during the complex cooling operation according to step S70, the controller 220 controls the second control valve 240 in accordance with the condensation pressure of the first condenser 122 or the second condenser 132 to the first, second condenser ( Adjusting the flow rate of the cooling water supplied to the 122,132 (S111) may be further included.

The step S111 is a process to allow the condensation of the refrigerant formed in the first condenser 122 and the second condenser 132 to be performed under a constant condensation pressure, and the condensation pressure or the second condenser 132 of the first condenser 122 is adjusted. When the condensation pressure of the lower than the predetermined condensation pressure set value, the controller 220 detects this to reduce the flow rate of the cooling water supplied to the first condenser 122 and the second condenser 132 (the second control valve ( Control is made.

When the flow rate of the cooling water supplied to the first condenser 122 and the second condenser 132 is reduced by the control operation of the controller 220, the condensation temperature and the condensation pressure of the first and second condensers 122 and 132 are reduced. Since it rises, the condensation pressure of the first and second condensers 122 and 132 can be maintained at a constant level by adjusting the flow rate of the cooling water supplied to the first and second condensers 122 and 132.

The step S80 is performed when the coolant temperature is not greater than the coolant temperature lower limit value TW2 as a result of the determination in step S60. The controller 220 is configured to partially close the first bypass pipe 170 according to the air supply temperature. By controlling the first control valve 180 to maintain the temperature of the air supply to a constant level by adjusting the flow rate of the cooling water supplied to the cooling water coil 150 regardless of the temperature change of the outside air, the first and second refrigeration systems (120, 130) By stopping, the hybrid air conditioning system is operated as a natural cooling operation system.

The step S80 is performed in the winter when the temperature of the outside air is low, and the cooling water from the winter cooling tower 140 is formed at a temperature low enough to cool the air supply, and thus, the first control valve 180 controls the first control valve 180. While partially closing the flow path of the bypass pipe 170, a part or all of the cooling water is supplied to the cooling water coil 150 to cool the air supply, and the first and second refrigeration systems 120 and 130 are stopped or remain stopped. Let's go.

As described above, the first control valve 180 operated by the controller 220 in the process of operating the hybrid outdoor air cooling system as a natural cooling operation system through the control according to step S80 controls the coolant coil 150 in response to the air supply temperature. ) And the first bypass pipe 170, but by appropriately adjusting the ratio of the cooling water distributed to the cooling water coil 150 and the first bypass pipe 170 in accordance with the change in the air supply temperature to a certain level. Is maintained.

On the other hand, it is preferable to ensure that the coolant flowing through the cooling water circulation pipe 160 always passes through the first and second condensers 122 and 132 in the process of operating the hybrid air cooling system as a natural cooling operation system through the step S80. In order to close the second bypass pipe 230 is 100%.

This is because when the coolant is not supplied to the first and second condensers 122 and 132 due to the stop of the first and second refrigeration systems 120 and 130 during the operation of the hybrid outdoor air cooling system as the natural cooling operation system, the first and second condensers ( 122, 132 maintains a room temperature state, and in this state, when the first and second refrigeration systems 120 and 130 start to restart, the standby time is required until the refrigerant discharged from the compressor is normally condensed in the condenser. There is a problem that is required.

However, when the first and second refrigeration systems 120 and 130 are stopped and the cooling water is supplied to the first and second condensers 122 and 132 even during the period of cooling through precooling, the first and second condensers As the 122 and 132 maintains a low temperature at all times, the condensation environment of the refrigerant is immediately generated when the first and second refrigeration systems 120 and 130 are restarted, thereby shortening the arrival time of the normal operation of the refrigeration system.

As described above, the hybrid outside air cooling system according to the present invention performs the cooling of the computer center by using a refrigeration system using a refrigerant compressor in the summer, but in the season and winter to cool the computer center by using cold outside air Energy can be saved.

In addition, the control method optimized for the computer center can obtain a larger energy saving effect than the general air cooling system, and the operation of the compressor is stabilized to prevent frequent failure of the compressor.

The present invention is not limited to the above-described specific preferred embodiments, and various modifications can be made by any person having ordinary skill in the art without departing from the gist of the present invention claimed in the claims. Of course, such changes will fall within the scope of the claims.

<Explanation of symbols for the main parts of the drawings>
110: evaporator 120: first refrigeration system
121: first compressor 122: first compressor
123: first expansion side 130: second refrigeration system
131: second compressor 132: second condenser
133: second expansion side 140: cooling tower
150: cooling water coil 160: cooling water circulation piping
161: coolant supply line 162: coolant return line
170: first bypass pipe 180: first control valve
190: air supply temperature sensor 200: ventilation temperature sensor
210: coolant temperature sensor 220: controller
230: second bypass pipe 240: second control valve
250: third bypass pipe 260: first capacity control valve
270: fourth bypass pipe 280: second capacity control valve

Claims (8)

An evaporator 110 which induces cooling of the air supply through heat exchange between the air supply and the refrigerant supplied to the computer center;
A first refrigeration system (120) constituted by a first compressor (121), a first condenser (122), a first expansion valve (123), and the evaporator (110);
A second refrigeration system (130) constituted by a second compressor (131), a second condenser (132), a second expansion valve (133), and the evaporator (110);
Cooling tower 140 for heat-exchanging the cooling water used for the condensation of the refrigerant in the first condenser 122 and the second condenser 132 with the outside;
A cooling water coil 150 disposed in front of the evaporator 110 to face the air supply before the evaporator 110 to cool the air supply through heat exchange between the cooling water and the air supply;
A cooling water circulation pipe 160 installed to connect the cooling tower 140 with the cooling water coil 150 and the first and second condensers 122 and 132 to circulate the cooling water;
A first bypass pipe 170 installed in the cooling water circulation pipe 160 so that the cooling water flowing through the cooling water circulation pipe 160 can flow without passing through the cooling water coil 150;
A first control valve 180 installed at a connection point between the first bypass pipe 170 and the cooling water circulation pipe 160 to control the flow of the cooling water;
An air supply temperature sensor 190 for detecting a temperature of the air supply supplied to the computer center;
A ventilation temperature sensor 200 for detecting a temperature of the ventilation discharged from the computer center;
A coolant temperature sensor 210 installed in the coolant circulation pipe 160 to detect a temperature of the coolant;
A second bypass pipe 230 connecting the cooling water supply line 161 constituting the cooling water circulation pipe 160 and the cooling water return line 162;
A second control valve 240 installed at a connection point between the cooling water circulation pipe 160 and the second bypass pipe 230 to control the flow of the cooling water; And
A function of controlling the first control valve 180 in response to a result of comparing the detected air supply temperature with a preset air supply temperature set value, and a result of comparing the detected coolant temperature with a preset coolant temperature upper limit value and a lower limit value; When the ventilation temperature detected by the sensor 200 is equal to or greater than a preset ventilation temperature setting value, a function of operating the first compressor 121 and a comparison between the air supply temperature and the air supply temperature setting value after the operation of the first compressor 121 may be compared. When the air supply temperature is higher than the air supply temperature set value through the additional operation of the second compressor 131, and corresponding to the condensation pressure of the first condenser 122 and the second condenser 132, the second control valve 240 Hybrid outdoor air-conditioning system using natural energy, comprising: a controller (220) having a function of controlling the flow rate of the cooling water supplied to the first and second condensers (122,132). delete The method according to claim 1,
A third bypass pipe 250 for supplying a portion of the high-temperature, high-pressure refrigerant gas discharged from the first compressor 121 to the rear end of the first expansion side 123;
A first capacity control valve 260 installed in the third bypass pipe 250 to control a flow rate of the refrigerant gas bypassed while controlling a flow path of the third bypass pipe 250;
A fourth bypass pipe 270 for supplying a part of the high-temperature, high-pressure refrigerant gas discharged from the second compressor 131 to the rear end of the second expansion side 133;
A second capacity control valve 280 installed in the fourth bypass pipe 270 and controlling a flow rate of the refrigerant gas bypassed while controlling a flow path of the fourth bypass pipe 270;
When the detected air supply temperature is lower than the preset capacity control valve operating temperature value TC, the controller 220 opens the first capacity control valve 260 and the second capacity control valve 280 to supply the refrigerant gas at a high temperature and high pressure. Hybrid outdoor air cooling system using natural energy, characterized in that the air supply temperature is further increased by supplying the rear end of the first and second expansion sides (123,133). In controlling the hybrid outside air cooling system using natural energy according to any one of claims 1 and 3,
Setting an air supply temperature set value TA1, a ventilation temperature set value TA2, a coolant temperature upper limit value TW1, a coolant temperature lower limit value TW2, and a capacity control valve operating temperature value TC (S10);
Comparing the air supply temperature detected by the air supply temperature sensor 190 with the air supply temperature set value TA1 to determine whether the detected air supply temperature is smaller than the air supply temperature set value TA1 (S20);
When the air supply temperature is smaller than the air supply temperature set value TA1, the first control valve 180 is controlled to open the first bypass pipe 170 at 100%, and the first and second refrigeration systems 120 and 130 are stopped. Performing a blowing operation (S30);
When the air supply temperature is not smaller than the air supply temperature set value TA1, the coolant temperature detected by the coolant temperature sensor 210 and the coolant temperature upper limit value TW1 are compared to determine whether the coolant temperature is greater than the coolant temperature upper limit value TW1. Step S40;
When the coolant temperature is greater than the coolant temperature upper limit value TW1 as a result of the determination in step S40, the first control valve 180 is controlled to open the first bypass pipe 170 at 100%, and the first and second refrigeration systems 120 and 130 are used. Performing a general cooling operation for cooling the air supply through the operation of the step (S50);
Determining whether the coolant temperature is greater than the coolant temperature lower limit value TW2 when the coolant temperature is not greater than the coolant temperature upper limit value TW1 (S60);
If the coolant temperature is greater than the coolant temperature lower limit value TW2 as a result of the determination in step S60, the coolant supplied from the cooling tower 140 is controlled by controlling the first control valve 180 to close the first bypass pipe 170 at 100%. Cooling the air supply while passing through the cooling water coil 150, and performing a combined cooling operation for cooling the air supply through the operation of the first and second refrigeration systems (120, 130) (S70); And
If the coolant temperature is not greater than the coolant temperature lower limit value TW2 as a result of the determination in step S60, the cooling tower 140 is controlled by controlling the first control valve 180 to partially close the first bypass pipe 170 according to the air supply temperature. Cooling water supplied from the cooling water to pass through the cooling water coil (150), and stopping the first and second refrigeration system (120,130) to perform a natural cooling operation (S80); natural energy characterized in that consisting of Hybrid air conditioning system control method using. The method according to claim 4,
The step S50 and S70,
Determining whether the ventilation temperature detected by the ventilation temperature sensor 200 is greater than the ventilation temperature set value TA2 (S91);
As a result of the determination in step S91, when the ventilation temperature is greater than the ventilation temperature set value TA2, cooling the air supply by operating the first refrigeration system 120 through the operation of the first compressor 121 (S92);
After the step S92, determining whether the air supply temperature detected by the air supply temperature sensor 190 is greater than the air supply temperature set value TA1 (S93);
As a result of the determination in step S93, if the air supply temperature is greater than the air supply temperature set value TA1, the second refrigeration system 130 is additionally operated through the operation of the second compressor 131, and then repeated again from the step S93. Step S94; And
As a result of the determination in step S93, if the air supply temperature is smaller than the air supply temperature set value TA1, repeating from step S91 again (S95); to sequentially operate the first and second refrigeration systems (120, 130) through Hybrid outdoor air conditioning system control method using the natural energy. The method according to claim 4,
During operation of the first compressor 121 for the operation of the first refrigeration system 120, the supply air temperature is compared with the supply air temperature detected by the air supply temperature sensor 190 and the capacity control valve operating temperature value TC. If the control valve is smaller than the operating temperature value TC, the high-temperature, high-pressure refrigerant gas discharged from the first compressor 121 is supplied to the rear end of the first expansion valve 123 through the opening of the first capacity control valve 260. Increasing the temperature of the device (S101); And
During operation of the second compressor 131 for operating the second refrigeration system 130, the supply air temperature is compared with the supply air temperature detected by the air supply temperature sensor 190 and the capacity control valve operating temperature value TC. If the control valve is smaller than the operating temperature value TC, the high-temperature, high-pressure refrigerant gas discharged from the second compressor 131 through the opening of the second capacity control valve 280 is supplied to the rear end of the second expansion valve 133 to supply air. Increasing the temperature of the step (S102); Control method of a hybrid outdoor air conditioning system using natural energy further comprising. The method according to claim 4,
In the process of performing the natural cooling operation through the step S80, the cooling water flowing through the cooling water circulation pipe 160 is always passed through the first and second condensers 122 and 132 so that the first refrigeration system 120 or the second refrigeration system is performed. The control method of the hybrid outside air cooling system using natural energy, characterized in that the condensation environment of the refrigerant is rapidly formed during operation of the 130, thereby shortening the arrival time of the normal operation of the first and second refrigeration systems (120, 130). The method according to claim 4,
During the combined cooling operation according to the step S70, the second control valve 240 is controlled to partially close the second bypass pipe 230 according to the condensation pressure of the first condenser 122 or the second condenser 132. Adjusting the flow rate of the cooling water supplied to the first and second condensers (122,132) (S111); Control method of a hybrid outside air cooling system using a natural energy.

Images