JP5724933B2 - Control device and heat pump device - Google Patents

Description

  The present invention relates to a control device for an electric device including a motor and a heat pump device including a fan motor.

  In heat pump devices, for example, fan motors and the like are increasingly demanded for brushless DC motors with high efficiency, long life and low electrical noise and mechanical noise. Such a multiphase motor such as a brushless DC motor is generally driven by being supplied with electric power from an inverter circuit with high energy efficiency.

  In a heat pump apparatus including such an inverter circuit, for example, as described in Patent Document 1 (Japanese Patent Laid-Open No. 5-114473), protection of the inverter circuit from overvoltage is achieved by a motor control circuit that controls the inverter circuit. And an overvoltage detection circuit. In order to protect the inverter circuit from overvoltage, the overvoltage detection circuit detects an overvoltage state of the inverter circuit, and the motor control circuit stops the operation of the inverter circuit based on the detection of the overvoltage state of the overvoltage detection circuit.

  By the way, in the heat pump apparatus, in addition to the inverter circuit and the motor control circuit of the fan motor, an actuator and a control device that operate by receiving power supply from an AC power supply for supplying power to the inverter circuit are provided. In order to protect such actuators and control devices, in addition to overvoltage detection circuits for fan motor inverter circuits, other detection circuits for detecting overvoltages or undervoltages of actuators and control devices are provided. In addition, malfunctions such as failure or malfunction of the control device due to overvoltage or undervoltage are prevented.

  However, as described above, when a detection circuit for detecting an overvoltage or an undervoltage is provided for each protection target and control is performed on the overvoltage or the undervoltage, the number of detection circuits is increased and the control device is an object to be controlled. The device is expensive.

  The subject of this invention is providing the control apparatus which can reduce the number of the detection apparatuses for detecting an overvoltage or an undervoltage about a control apparatus provided with the motor control part which controls an inverter circuit.

A control device according to a first aspect of the present invention is a control device for an electric device including a motor to which driving power is supplied by an inverter circuit, and is connected to a motor control unit for controlling the motor and the motor control unit. A main body control unit for controlling the electric device, and at least one of the motor control unit and the main body control unit is such that the DC bus voltage of the inverter circuit satisfies an overvoltage or undervoltage condition and the motor control state Determines that a voltage abnormality has occurred in the commercial power line to which the inverter circuit is connected. In addition, at least one of the motor control unit and the main body control unit determines whether to protect the inverter circuit compared to the DC bus voltage based on the first upper limit threshold voltage and compares it with the DC bus voltage. Whether the voltage abnormality of the commercial power line is determined based on the second upper limit threshold voltage, or whether to protect the inverter circuit compared with the DC bus voltage is determined based on the first lower limit threshold voltage and the DC bus The voltage abnormality of the commercial power line is determined based on the second lower limit threshold voltage as compared with the voltage.

  According to the control device of the first aspect, at least one of the motor control unit and the main body control unit is connected to a commercial power source by adding a predetermined condition of the control state of the motor to the detection of the overvoltage or undervoltage of the DC bus voltage. Since the line voltage abnormality can be determined, a detection device for detecting an overvoltage or an undervoltage of the commercial power supply line can be omitted.

Moreover, the type of abnormality can be specified by dividing the threshold value for detection. For example, by having the second upper limit threshold voltage that is the second threshold value for determining the voltage abnormality of the commercial power supply line, the second threshold value is used to determine only the voltage abnormality related to the overvoltage abnormality of the commercial power supply line. it can. Further, for example, by having a second lower limit threshold voltage that is a second threshold for determining a voltage abnormality of the commercial power supply line, the second threshold is used to determine only a voltage abnormality related to an insufficient voltage of the commercial power supply line. be able to.

  In the control device according to the second aspect of the present invention, in the control device according to the first aspect, when the motor control unit determines that a voltage abnormality has occurred in the commercial power line, the voltage abnormality of the commercial power line is detected. The signal shown is output to the main body controller.

  According to the control device according to the second aspect, conventionally, if the main body control unit has received a signal indicating a power supply abnormality from the detection device for detecting an overvoltage or undervoltage, the main body control unit receives the signal from the motor control unit. By receiving a signal indicating a power supply abnormality, the configuration is similar to the conventional one, and the number of detection devices for detecting overvoltage or undervoltage can be reduced without changing the configuration of the main body control unit.

  A control device according to a third aspect of the present invention is the control device according to the first aspect, wherein the motor control unit sends a voltage signal related to the DC bus voltage to the main body control unit, and the main body control unit outputs the voltage related to the DC bus voltage. The occurrence of voltage abnormality in the commercial power line is determined based on the signal.

  According to the control device according to the third aspect, since the main body control unit only needs to receive a voltage signal from the motor control unit in order to determine the voltage abnormality, the overvoltage or the undervoltage can be reduced without increasing the number of terminals of the main body control unit. The number of detection devices for detection can be reduced.

  A control device according to a fourth aspect of the present invention is the control device according to any one of the first to third aspects, wherein the predetermined condition is before driving the motor or performs control to stop the motor. It is that you are.

  According to the control device according to the fourth aspect, since the predetermined condition is before the motor is driven or the control is performed so that the motor is stopped, the commercial power supply indicates that the motor is not driven. This is a condition for determining that a voltage abnormality has occurred in the line. With this configuration, it is possible to determine the voltage abnormality of the commercial power line in a state where the DC bus voltage is not affected by the driving of the motor.

  A control device according to a fifth aspect of the present invention is the control device according to any one of the first to fourth aspects, further comprising a DC bus connected to the inverter circuit and the commercial power supply line, and a motor control unit and main body control At least one of the units cuts off the connection between the commercial power line and the DC bus when it is determined that a voltage abnormality has occurred in the commercial power line.

  According to the control device of the fifth aspect, the connection between the commercial power supply line where the voltage abnormality has occurred and the direct current bus is cut off, and the direct current bus is disconnected from the commercial power supply line. Can be prevented from reaching the inverter circuit.

  A control device according to a sixth aspect of the present invention is the control device according to any one of the first to fifth aspects, wherein the main body control unit detects a voltage abnormality in the commercial power supply line based only on the DC bus voltage information of the inverter circuit It is determined whether or not this has occurred.

According to the control device according to the sixth aspect, since the main body control unit only receives the DC bus voltage information from the motor control unit, the terminals and lines of the main body control unit for inputting information for detecting voltage abnormality are connected. Ru can be omitted.

A heat pump device according to a seventh aspect of the present invention is a heat pump device connected to a commercial power supply line, and supplies a fan motor for generating a flow of air exchanged with a refrigerant and driving power to the fan motor. In order to control the fan motor connected to the inverter circuit and the voltage detector, the inverter circuit connected to the commercial power line, the voltage detector for detecting the DC bus voltage of the inverter circuit and detecting the abnormality The fan motor control unit, the main body control unit for controlling the heat pump device connected to the fan motor control unit, and the DC bus voltage of the inverter circuit are driven by power supplied from a commercial power line in a different system, and an actuator other than the fan motor, at least one of the fan motor control unit and the main body control unit When control state condition satisfied and the fan motor of the DC bus voltage overvoltage or undervoltage inverter circuit also satisfy a predetermined condition, the voltage abnormality is judged to be occurring in the commercial power line. Further, the main body control unit uses information on the DC bus voltage of the inverter circuit to determine whether or not an abnormality has occurred in the actuator.

According to the heat pump device according to the seventh aspect , at least one of the fan motor control unit and the main body control unit is added by adding a predetermined condition of the control state of the fan motor to the detection of the overvoltage or undervoltage of the DC bus voltage. Since the voltage abnormality of the commercial power line can be determined, it is possible to omit a detection device for detecting an overvoltage or an undervoltage for detecting a voltage abnormality of the commercial power line.

In addition, since the information on the DC bus voltage of the inverter circuit is used to determine whether or not an abnormality has occurred in the actuator, the DC bus of the inverter circuit is included in the information necessary to determine whether or not an abnormality has occurred in the actuator. For the information that can be confirmed from the information obtained from the voltage, a detection device for obtaining the information becomes unnecessary.

A heat pump device according to an eighth aspect of the present invention is a heat pump device connected to a commercial power line, and supplies a fan motor for generating a flow of air that exchanges heat with a refrigerant, and driving power to the fan motor. In order to control the fan motor connected to the inverter circuit and the voltage detector, the inverter circuit connected to the commercial power line, the voltage detector for detecting the DC bus voltage of the inverter circuit and detecting the abnormality A fan motor control unit, a main unit control unit connected to the fan motor control unit for controlling the heat pump device, a control power source functioning as a power source for the main unit control unit, and a DC bus voltage of the inverter circuit are commercialized in different systems Connected to an actuator other than a fan motor driven by power supplied from the power line and a commercial power line Which is controlled by the main control unit comprises a switch capable of disconnecting at least one of the inverter circuit and the actuator from the commercial power line, a, of the fan motor control unit and the main body control unit at least one of, the inverter circuit When the DC bus voltage satisfies the overvoltage or undervoltage condition and the fan motor control state also satisfies the predetermined condition, it is determined that a voltage abnormality has occurred in the commercial power supply line, and the main body control unit When it is determined that a voltage abnormality has occurred, at least one of the inverter circuit and the actuator is disconnected from the commercial power supply line by a switch so as not to stop power supply to the control power supply .

A heat pump device according to a ninth aspect of the present invention is the heat pump device according to the eighth aspect, wherein the control power supply is connected to the commercial power supply line through a system different from the DC bus voltage of the inverter circuit, and the switch is connected to the control power supply. It is connected to the commercial power line at the latter stage.

  A heat pump device according to a tenth aspect of the present invention is a heat pump device connected to a commercial power supply line, an indoor fan motor for generating a flow of air exchanged with a refrigerant, and driving power for the indoor fan motor An inverter circuit connected to a commercial power line to supply power, a voltage detection unit for detecting an abnormality by detecting a DC bus voltage of the inverter circuit, and an indoor fan motor connected to the inverter circuit and the voltage detection unit Connected to the fan motor control unit, the main body control unit for controlling the heat pump device, and driven by the power supplied from the commercial power line in a system different from the DC bus voltage of the inverter circuit An outdoor unit, and a switch (91) capable of disconnecting power supply from a commercial power line to the outdoor unit, And at least one of the fan motor control unit and the main body control unit is configured to supply a commercial power line when the DC bus voltage of the inverter circuit satisfies an overvoltage or undervoltage condition and the indoor fan motor control state also satisfies a predetermined condition. When the main body control unit determines that a voltage abnormality has occurred in the commercial power line, the main body control unit disconnects the outdoor unit from the commercial power line by the switch.

In the heat pump device according to the eleventh aspect of the present invention, in the heat pump device according to any of the seventh to tenth aspects, when the fan motor control unit determines that a voltage abnormality has occurred in the commercial power line, A signal indicating a voltage abnormality of the commercial power supply line is output to the main body control unit.

A heat pump device according to a twelfth aspect of the present invention is the heat pump device according to any one of the seventh to eleventh aspects, wherein the fan motor control unit sends a voltage signal related to the DC bus voltage to the main body control unit, and the main body control The unit determines the occurrence of a voltage abnormality in the commercial power supply line based on a voltage signal related to the DC bus voltage.

The heat pump device according to a thirteenth aspect of the present invention is the heat pump device according to any one of the seventh to twelfth aspects, wherein the predetermined condition is before driving the fan motor or control for stopping the fan motor. Is to do.

A heat pump device according to a fourteenth aspect of the present invention is the heat pump device according to any one of the seventh to thirteenth aspects, further comprising a DC bus connected to the inverter circuit and the commercial power supply line, and a fan motor control unit and a main body When at least one of the control units determines that a voltage abnormality has occurred in the commercial power supply line, the connection between the commercial power supply line and the DC bus is cut off.

A heat pump device according to a fifteenth aspect of the present invention is the heat pump device according to any one of the seventh to fourteenth aspects, wherein at least one of the fan motor control unit and the main body control unit is information on a DC bus voltage of the inverter circuit. Whether or not a voltage abnormality has occurred in the commercial power line is determined based on the above.

A heat pump device according to a sixteenth aspect of the present invention is the heat pump device according to any one of the seventh to fifteenth aspects, wherein at least one of the fan motor control unit and the main body control unit is an inverter compared to the DC bus voltage. Whether to protect the circuit is determined based on the first threshold value, and compared with the DC bus voltage, a voltage abnormality of the commercial power supply line is determined based on the second threshold value.

In the control device according to the first aspect of the present invention, the number of detection devices for detecting overvoltage or undervoltage can be reduced in the control target of the main body control unit. In addition, it is possible to improve the accuracy of the determination about the voltage abnormality of the commercial power line.

  In the control device according to the second aspect of the present invention, it is not necessary to change the configuration of the main body control unit, and an increase in the cost of the control device can be suppressed.

  In the control device according to the third aspect of the present invention, an increase in the number of terminals of the main body control unit can be suppressed, and an increase in the cost of the control device can be suppressed.

  In the control device according to the fourth aspect of the present invention, it is possible to eliminate the influence due to the driving of the motor, and therefore it is possible to improve the accuracy of the determination of the voltage abnormality of the commercial power supply line.

  In the control device according to the fifth aspect of the present invention, it is possible to prevent the inverter circuit from being damaged due to a voltage abnormality of the commercial power supply line.

  In the control device according to the sixth aspect of the present invention, the configuration of the main body control unit is simplified, and the cost required for the control device can be reduced.

In the heat pump device according to any one of the seventh to sixteenth aspects of the present invention, the number of detection devices for detecting overvoltage or undervoltage can be reduced in the control target of the main body control unit.

In the heat pump device according to the seventh aspect of the present invention, information necessary for determining whether an abnormality has occurred in the actuator, which can be confirmed from information obtained from the DC bus voltage of the inverter circuit, in the control target of the main body control unit. Can be simplified or reduced.

The perspective view which shows the external appearance of the air conditioning apparatus which concerns on one Embodiment. The circuit diagram which shows the refrigerant circuit of an air conditioning apparatus, and the outline | summary of the periphery. The perspective view for demonstrating the internal structure of an outdoor unit. The block diagram which shows the outline | summary of the control system by a control part. The circuit diagram which shows an example of an outdoor fan motor part, its power supply, and a peripheral circuit. The block diagram for demonstrating the function of a motor control part and a main-body control part. The flowchart which shows an example of the step of abnormality detection and control at the time of abnormality. The flowchart which shows the other example of the step of abnormality detection and control at the time of abnormality. The circuit diagram which shows the other example of an outdoor fan motor part, its power supply, and a peripheral circuit. The block diagram which shows the other example of the outdoor unit containing a motor control part and a main-body control part. The block diagram which shows the other example of the air conditioning apparatus containing a motor control part and a main-body control part.

  Hereinafter, the electric device of the present invention will be described by taking a heat pump type air conditioner as an example. The heat pump type air conditioner includes an outdoor fan motor unit, and the outdoor fan motor unit includes a brushless DC motor (hereinafter referred to as a brushless DC motor). In addition, the heat pump type air conditioner includes a control unit 50 including a motor control unit that controls the outdoor fan motor unit and a main body control unit that controls the device, particularly the outdoor unit 30.

(1) Outline of heat pump type air conditioner (1-1) Outline of configuration of air conditioner FIG. 1 shows an appearance of a heat pump type air conditioner (hereinafter referred to as an air conditioner) according to an embodiment of the present invention. It is a perspective view shown. The air conditioner 10 in FIG. 1 includes an indoor unit 20 and an outdoor unit 30. The outdoor unit 30 is connected to the indoor unit 20 installed indoors by a refrigerant pipe, and constitutes a refrigerant circuit of the air conditioner 10 together with the indoor unit 20. For this purpose, the indoor unit 20 and the outdoor unit 30 are connected to each other by a communication pipe 12 through which a refrigerant pipe, a communication line, a transmission line, and the like pass.

  FIG. 2 is a circuit diagram showing an outline of the configuration of the air conditioning apparatus 10 of FIG. In FIG. 2, a solid line connecting the devices indicates a refrigerant pipe, and a broken line connecting the devices indicates a signal transmission line. In order to configure the refrigerant circuit 14 shown in FIG. 2, the indoor unit 20 is provided with an indoor heat exchanger 21 and the like, and the outdoor unit 30 includes a compressor 31, a four-way switching valve 32, and an outdoor heat exchanger 33. A motor-operated valve 34 and an accumulator 35 are provided.

  Here, the circuit configuration of the refrigerant circuit 14 will be briefly described. A first port of a four-way switching valve 32 is connected to the discharge side of the compressor 31. One outlet of the outdoor heat exchanger 33 is connected to the second port of the four-way switching valve 32, the accumulator 35 is connected to the third port, and the refrigerant communication pipe 12b is connected to the fourth port. The four-way switching valve 32 is connected to the first port and the second port as shown by the solid line during cooling and to the third port and the fourth port. The four-way switching valve 32 is connected to the first port and the second port as shown by the solid line during cooling and to the third port and the fourth port. On the other hand, at the time of heating, as shown by the broken line, the four-way switching valve 32 is connected to the first port and the fourth port and to the second port and the third port. The other entrance / exit of the outdoor heat exchanger 33 is connected to one entrance / exit of the indoor heat exchanger 21 via the electric valve 34 and the refrigerant communication pipe 12a. The other entrance / exit of the indoor heat exchanger 21 is connected to the fourth port of the four-way switching valve 32 via the refrigerant communication pipe 12b. Further, the suction side of the compressor 31 is connected to the third port of the four-way switching valve 32 via the accumulator 35. The refrigerant circulates in the refrigerant circuit 14.

(1-2) Outline of the operation of the air conditioner During cooling, the four-way switching valve 32 is switched to a solid line connection, and the refrigerant compressed and discharged by the compressor 31 passes through the four-way switching valve 32 to generate outdoor heat. It is sent to the exchanger 33. During cooling, the outdoor heat exchanger 33 functions as a condenser, and the refrigerant that has been deprived of heat by exchanging heat with the outside air by condensation is sent to the motor-operated valve 34. The motor-operated valve 34 functions as an expansion valve, and the high-pressure liquid refrigerant changes to a low-pressure wet steam state. Thus, the refrigerant expanded by the electric valve 34 enters the indoor heat exchanger 21 through the refrigerant communication pipe 12a. During cooling, the indoor heat exchanger 21 functions as an evaporator, heat exchange is performed between the indoor air and the refrigerant by evaporation, and the refrigerant whose temperature has risen due to the heat of the indoor air passes through the refrigerant communication pipe 12a. It is sent to the four-way switching valve 32. The four-way switching valve 32 is switched so that the refrigerant communication pipe 12a and the accumulator 35 are connected. Therefore, the refrigerant sent from the indoor heat exchanger 21 is sent to the accumulator 35 connected to the suction side of the compressor 31 by the four-way switching valve 32.

  During heating, the four-way switching valve 32 is switched to a dotted connection, and the refrigerant compressed and discharged by the compressor 31 serves as a condenser from the four-way switching valve 32 via the refrigerant communication pipe 12b. 21. And the refrigerant | coolant which came out of the outdoor heat exchanger 33 which functions as an evaporator along the path | route reverse to the time of air_conditioning | cooling is sent to the compressor 31. FIG. That is, from the compressor 31, the four-way switching valve 32, the refrigerant communication pipe 12b, the indoor heat exchanger 21, the refrigerant communication pipe 12a, the electric valve 34, the outdoor heat exchanger 33, the four-way switching valve 32, and the accumulator 35 are sequentially passed. The refrigerant circulates along the path returning to the compressor 31.

  The indoor unit 20 and the outdoor unit 30 include an indoor fan 22 that sends room air to the indoor heat exchanger 21 and an outdoor heat exchanger in order to promote heat exchange in the indoor heat exchanger 21 and the outdoor heat exchanger 33, respectively. A propeller fan 37 for sending outside air to 33 is provided. An indoor fan motor unit 23 and an outdoor fan motor unit 38 for driving the indoor fan 22 and the propeller fan 37 are provided in the indoor unit 20 and the outdoor unit 30, respectively.

(1-3) Structure of Outdoor Unit As shown in FIG. 1, the outdoor unit 30 has a substantially rectangular parallelepiped shape and is covered with a casing 15. A front plate assembly 16 is disposed on the front surface of the casing 15, and the front plate assembly 16 is provided with a fan outlet 17 at a substantially central portion thereof.

  FIG. 3 shows the outdoor unit 30 with the casing 15 removed. The outdoor heat exchanger 33 is exposed from the back surface of the casing 15 to one side surface. The propeller fan 37 is disposed immediately on the back side of the fan outlet 17, and the outdoor fan motor unit 38 that drives the propeller fan 37 is disposed on the back side of the propeller fan 37. The outside air sucked from the back surface and one side surface of the casing 15 passes through the outdoor heat exchanger 33 and is blown out from the fan outlet 17 on the front surface of the casing 15.

  The airflow blown out from the fan outlet 17 is generated when the propeller fan 37 is driven by the outdoor fan motor 38a and the propeller fan 37 rotates counterclockwise (CCW direction). Even when the propeller fan 37 is not driven by the outdoor fan motor unit 38, an external force generated by an external airflow generated outside may act on the propeller fan 37 to generate torque that rotates the propeller fan 37. For example, when an external airflow passes through the fan outlet 17 in the direction of the outdoor heat exchanger 33, the propeller fan 37 rotates clockwise (CW direction) by torque generated in the propeller fan 37 by the external airflow.

(2) Control system (2-1) Outline of control system The indoor unit 20 and the outdoor unit 30 are incorporated in each device in order to perform the air conditioning operation in the air conditioning apparatus 10 correctly and efficiently. It is controlled by the indoor control unit 60 and the outdoor control unit 70. FIG. 4 is a block diagram showing an outline of the configuration of the control system. The indoor control unit 60 and the outdoor control unit 70 are connected to each other via the communication line 12c to transmit / receive data to / from each other, and constitute one control device 50. The control device 50 includes a CPU (Central Processing Unit), a memory, peripheral circuits, and the like, and realizes a control function described later by combining these circuits.

  The outdoor unit 30 includes an outdoor heat exchanger temperature sensor 41, a heat exchanger inlet / outlet temperature sensor 42, a suction side temperature sensor 43, a discharge side temperature sensor 44, as temperature sensors for measuring the temperature of each part of the outdoor unit 30. An outdoor temperature sensor 45 and the like are provided, and temperature values measured by these temperature sensors 41 to 45 are transmitted to the outdoor control unit 70. The outdoor heat exchanger temperature sensor 41 measures the temperature of the refrigerant inside the outdoor heat exchanger 33. The heat exchanger inlet / outlet temperature sensor 42 provided at the inlet / outlet of the outdoor heat exchanger 33 measures the temperature of the refrigerant flowing between the outdoor heat exchanger 33 and the indoor unit 20. The suction side temperature sensor 43 measures the temperature of the refrigerant sucked into the compressor 31. The discharge side temperature sensor 44 measures the temperature of the refrigerant discharged from the compressor 31. The outside temperature sensor 45 measures the outside temperature around the outdoor unit 30.

  The outdoor unit 30 includes a suction side pressure sensor 46 for measuring the pressure of the refrigerant sucked into the compressor 31, a discharge side pressure sensor 47 for measuring the pressure of the refrigerant discharged from the compressor 31, and the like. A pressure sensor is provided. The refrigerant pressure values measured by the suction side pressure sensor 46 and the discharge side pressure sensor 47 are transmitted to the outdoor control unit 70.

  Further, in the outdoor unit 30, the compressor motor unit 40, the four-way switching valve 32, the electric valve 34, and the outdoor fan motor unit 38 of the compressor 31 are connected to the outdoor control unit 70. The outdoor control unit 70 controls the rotation speed of the compressor motor unit 40 and the outdoor fan motor unit 38 and their operation / stop, controls the switching of the four-way switching valve 32, and controls the opening degree of the electric valve 34. Is done.

  The indoor unit 20 is provided with a liquid side temperature sensor 24 and a gas side temperature sensor 25 for measuring the temperature of the refrigerant at the entrance and exit of the indoor heat exchanger 21, and an indoor temperature sensor 26 for measuring the indoor temperature. Is provided. Signals indicating the temperature values measured by these temperature sensors 24 to 26 are transmitted to the indoor control unit 60. In the indoor unit 20, the indoor fan motor unit 23 of the indoor fan 22, the wind direction adjusting mechanism 27, the display unit 28, and the like are connected to the indoor control unit 60. The indoor controller 60 controls the rotation speed and operation / stop of the indoor fan motor unit 23. The direction of the wind blown into the room is adjusted by the air direction adjusting mechanism 27 changing the angle of a louver (not shown) provided in the indoor unit 20. The indoor control unit 60 outputs a control signal for instructing display to the display unit 28 in order to perform various displays. For example, the control device 50 can cause the display unit 28 to display an abnormality report when an abnormality occurs in the outdoor fan motor unit 38 described later.

(2-2) Configuration of Outdoor Fan Motor Unit and its Periphery FIG. 5 shows the outdoor fan motor unit, the motor control unit, and the configuration of their periphery. Electric power is supplied to the outdoor fan motor unit 38 from a commercial AC power supply 48. Commercial power supply lines 48a and 48b of the commercial AC power supply 48 are connected to the rectifier circuit 49B. The rectifying circuit 49B includes a rectifying unit 495 made of a diode and a smoothing capacitor 496 connected between the high-voltage side DC bus line 498 and the low-voltage side DC bus line 499. The DC bus voltage rectified by the rectifier circuit 49B is supplied to the outdoor fan motor unit 38 through DC bus lines 498 and 499.

  The outdoor fan motor 38a of the outdoor fan motor unit 38 shown in FIG. 5 is a brushless DC motor. The drive voltages Vu, Vv, Vw of the outdoor fan motor 38a are output from the inverter circuit 38b that receives supply of the DC bus voltage from the DC bus lines 498, 499. The outdoor fan motor 38a includes a rotor 381, a stator 382, and three hall elements 54a, 54b, and 54c.

  The stator 382 has a star connection in which one ends of the armature coils Lu, Lv, and Lw are commonly connected at a neutral point n. The rotor 381 coupled to the propeller fan 37 has a multipolar permanent magnet. The rotor 381 rotates relative to the stator 382 by the electromagnetic force generated between the permanent magnet and the armature coils Lu, Lv, Lw, with the rotation axis as the center. In order to rotate the outdoor fan motor 38a, drive voltages Vu, Vv, Vw are output from the inverter circuit 38b to the armature coils Lu, Lv, Lw.

  The inverter circuit 38b includes upper arm insulated gate bipolar transistors Q1, Q2, and Q3 connected between the other ends of the armature coils Lu, Lv, and Lw and the high-voltage side DC bus line 498, and these The lower arm insulated gate bipolar transistors Q4, Q5, and Q6 connected between the other end of the armature coils Lu, Lv, and Lw and the DC bus line 499 on the low voltage side are provided as switching elements. Hereinafter, the insulated gate bipolar transistor Q1 is abbreviated as the transistor Q1, and the insulated gate bipolar transistors Q2 to Q6 are similarly described. Free-wheeling diodes D1, D2, D3, D4, D5, and D6 are connected in antiparallel to the transistors Q1, Q2, Q3, Q4, Q5, and Q6, respectively. Each of the free-wheeling diodes D1 to D6 is turned on when a reverse voltage is applied to the transistors Q1 to Q6 to which each of the free-wheeling diodes D1 to D6 is connected, and protects the transistors Q1 to Q6 from the reverse voltage.

  The inverter circuit 38b turns on the upper arm transistors Q1, Q2, and Q3, thereby turning the armature coils Lu, Lv, and V from the high-voltage side DC bus line 498 through the transistors Q1, Q2, and Q3. A high voltage is applied to the other end of Lw. The inverter circuit 38b also turns on the lower arm transistors Q4, Q5, and Q6 to turn on the armature coils Lu, from the low-voltage side DC bus line 499 via the transistors Q4, Q5, and Q6. A low voltage is applied to the other ends of Lv and Lw.

  The outdoor fan motor unit 38 is provided with a voltage detection unit 81 and a current detection unit 82. An overvoltage between the DC bus lines 498 and 499 is detected by the voltage detection unit 81 connected between the DC bus lines 498 and 499. Such a voltage detection unit 81 is provided with a plurality of detection circuits including, for example, a plurality of resistors connected between the DC bus lines 498 and 499 and a transistor for detecting a voltage applied to one of the resistors. Consists of. By adopting this configuration, an appropriate detection circuit can be selected from a plurality of detection circuits that detect an overvoltage with different threshold voltages according to a signal given from the motor control unit 74. Thereby, the voltage detection unit 81 can switch the threshold voltage for detecting the overvoltage when outputting the detection of the overvoltage to the motor control unit 74.

  Further, an overcurrent flowing through the outdoor fan motor unit 38 is detected by the current detection unit 82 inserted in series in the DC bus line 499 on the low voltage side. The current detection unit 82 is a detection circuit including, for example, a shunt resistor inserted in the DC bus line 499, an amplifier circuit including an operational amplifier that amplifies the voltage across the shunt resistor, and a transistor that detects an output voltage of the amplifier circuit. Composed.

  The outdoor fan motor unit 38 is provided with a discharge unit 497 and is controlled by the outdoor control unit 70. The discharging unit 497 discharges the smoothing capacitor 496 to adjust the voltage between the high voltage side DC bus line 498 and the low voltage side DC bus line 499.

(2-3) Control of Inverter Circuit The motor control unit 74 for controlling the outdoor fan motor unit 38 includes a gate control voltage generation unit 741, a PWM (Pulse-Width Modulation) control unit 742, and a rotation direction detection unit 743. A rotation speed measurement unit 744, a discharge control unit 746, and an overcurrent protection unit 747 are included.

[Gate control voltage generator]
As shown in FIG. 5, the gate control voltage generator 741 outputs six gate control voltages Gu, Gv, Gw, Gx, Gy, Gz for controlling on / off of the transistors Q1 to Q6 of the inverter circuit 38b. To do. The gate control voltages Gu, Gv, Gw, Gx, Gy, Gz output from the gate control voltage generation unit 741 cause the drive voltages Vu, Vv, Vw corresponding to the PWM control signal v_duty output from the PWM control unit 742 to be rotors. It is output from the inverter circuit 38b to the outdoor fan motor 38a at a timing based on the position.

[PWM control unit]
The PWM control unit 742 determines a duty value and the like based on the rotation direction and the rotation speed of the outdoor fan motor 38a, and outputs a PWM control signal v_duty for performing pulse width modulation to the gate control voltage generation unit 741.

(Rotation direction detector)
The rotation direction detector 743 uses the position detection signals Hu, Hv, and Hw output from the hall elements 54a to 54c to rotate the rotor 381 in the outdoor fan motor 38a (hereinafter referred to as the rotation direction of the outdoor fan motor 38a). May be described). The rotation direction of the outdoor fan motor 38 a detected by the rotation direction detection unit 743 is taken into the PWM control unit 742.

[Rotation speed measurement unit]
The rotational speed measurement unit 744 uses the position detection signals Hu, Hv, and Hw output from the hall elements 54a to 54c to rotate the rotational speed of the rotor 381 in the outdoor fan motor 38a (hereinafter referred to as the rotational speed of the outdoor fan motor 38a). (It may be described)). The measured rotation speed of the outdoor fan motor 38 a is taken into the PWM control unit 742.

(Discharge control unit)
The discharge control unit 746 controls the discharge unit 497. Specifically, the discharge controller 746 discharges at least a part of the electric charge accumulated in the smoothing capacitor 496 when the DC bus voltage Vdc detected by the voltage detector 81 exceeds the first upper limit threshold voltage. Thus, the discharge unit 497 is controlled. For example, the discharge control unit 746 determines the amount of charge to be discharged based on the difference between the first upper limit threshold voltage and the DC bus voltage Vdc, and determines the time for the discharge unit 497 to discharge from the determined amount of charge. . Here, the first upper threshold voltage is determined by the ratings of the transistors Q1 to Q6 and the like in the inverter circuit 38b.

  When the voltage detection unit 81 detects that the DC bus voltage Vdc has been boosted and exceeds the first upper limit threshold voltage, the voltage detection unit 81 notifies the discharge control unit 746 that the first upper limit threshold voltage has been exceeded. The discharge control unit 746 causes the discharge unit 497 to discharge. Then, since the amount of charge accumulated in the smoothing capacitor 496 is reduced, the DC bus voltage Vdc is suppressed to a value below the rating of each of the transistors Q1 to Q6 in the inverter circuit 38b. In this way, the discharge control unit 746 adjusts the voltage across the smoothing capacitor 496 based on the voltage detected by the voltage detection unit 81, and the DC bus voltage Vdc is rated for the transistors Q1 to Q6 of the inverter circuit 38b. When there is a risk of exceeding the voltage, control is performed so that the DC bus voltage Vdc falls below the rated voltage.

[Overcurrent protection section]
The overcurrent protection unit 747 adjusts the current flowing through the outdoor fan motor 38a based on the current detected by the current detection unit 82 so as not to exceed the rated current of the transistors Q1 to Q6 of the inverter circuit 38b. For example, when the current value detected by the current detection unit 82 exceeds the threshold current, the overcurrent protection unit 747 outputs a signal instructing the gate control voltage generation unit 741 to stop driving the inverter circuit 38b. .

(2-4) Motor control unit and main body control unit In addition to the motor control unit 74, the outdoor control unit 70 includes a compressor motor control unit 76 and a compressor motor control unit 76 for controlling the compressor motor unit 40. A main body control unit 75 for controlling the above-described four-way switching valve 32, the electric valve 34, and the like is included (see FIGS. 5 and 6). Information necessary for control is exchanged between the main body control unit 75 and the motor control unit 74. The target rotational speed of the outdoor fan motor 38a is calculated by the main body control unit 75 from various conditions such as the set temperature of heating and cooling, the environmental temperature, and the like. A rotation speed command signal rd for instructing the rotation speed is output.

  On the other hand, the motor control unit 74 outputs a signal rm indicating the rotation number measured by the rotation number measurement unit 744 to the main body control unit 75. In addition, voltage abnormality signals Varm1 and Varm2 indicating abnormality of the DC bus voltage Vdc are output from the motor control unit 74 to the main body control unit 75.

(3) Supply of electric power to each part of the outdoor unit The outdoor unit 30 is connected to the commercial AC power supply 48 as shown in FIG. 6, and the four-way switching valve 32 and the electric motor are connected by the commercial power lines 48a and 48b. Electric power is supplied to the valve 34, the rectifier circuits 49A and 49B, the control power supply 71, and the like. The rectifying circuit 49A includes a rectifying unit 491 made of a diode, and a smoothing capacitor 492 connected between the high-voltage side DC bus line 493 and the low-voltage side DC bus line 494. The compressor motor unit 40 is connected to the DC bus lines 493 and 494 of the rectifier circuit 49A. The compressor motor unit 40 includes a compressor motor 40a and an inverter circuit 40b. The control power supply 71 is a power supply for the outdoor control unit 70.

  The commercial power line 48a and the rectifier circuit 49B are connected via an electromagnetic contactor 90. The electromagnetic contactor 90 is controlled by the main body control unit 75 and used to disconnect the rectifier circuit 49B from the commercial power line 48a when an abnormality occurs in the commercial power line 48a.

(4) Voltage Abnormality Detection of Motor Control Unit and Main Body Control Unit Voltage abnormality detection in the motor control unit 74 will be described along the flowchart of FIG. The motor control unit 74 is configured to transmit an operation start signal when the operation of the air conditioner 10 is instructed to the control device 50 and the operation is started. The motor control unit 74 first determines whether or not the operation is started based on whether or not an operation start signal is transmitted from the main body control unit 75 to the motor control unit 74 (step S1).

  If the operation start instruction has not been received, the outdoor fan motor unit 38 does not perform the control for rotating the outdoor fan motor 38a, that is, the drive control is not performed (the control is performed to stop the motor). The control unit 74 determines. In this case, the outdoor fan motor 38a may be rotated by the flow of outdoor air, but here, since the control for rotating the outdoor fan motor 38a is not performed, the outdoor fan motor 38a is not rotating. Then, the motor control unit 74 detects the voltage abnormality of the commercial AC power supply 48 described below (step S2).

  At this time, when the voltage detecting unit 81 detects that the DC bus voltage Vdc exceeds the first upper limit threshold voltage, the motor control unit 74 determines that an overvoltage is supplied from the commercial power supply lines 48a and 48b. (Step S3). Even if the DC bus voltage Vdc exceeds the first upper limit threshold voltage, the motor control unit 74 does not control the discharge control unit 497 with respect to the discharge control unit 497, and sends a voltage abnormality signal from the discharge control unit 746 to the main body control unit 75. Varm2 is output (step S4).

  When receiving the voltage abnormality signal Varm2, the main body control unit 75 opens the electromagnetic contactor 90 and disconnects the rectifier circuit 49B from the commercial power supply lines 48a and 48b (step S5). Further, when receiving the voltage abnormality signal Varm2, the main body control unit 75 transmits an abnormality notification signal indicating that an abnormality has occurred in the commercial power supply lines 48a and 48b to the indoor control unit 60, for example. Receiving the abnormality notification signal, the indoor control unit 60 displays on the display unit 28 of the indoor unit 20 that an abnormality has occurred in the commercial power supply lines 48a and 48b (step S6). With the end of the process in step 6, the series of processes from step S1 to step S6 before the start of operation ends.

  If it is determined in step S1 that the operation has started, the overvoltage of the outdoor fan motor unit 38 is processed by the processing in steps S8 to S11 until an instruction to end the operation is received (step S7), as in the conventional case. Anomaly detection is performed. First, when it is determined that the operation is started in step S1 and the process proceeds to step S7, it is natural that the operation end instruction is not received. Therefore, the process proceeds to step S8, and the motor control unit 74 performs the same as in the conventional case. Then, the abnormality of the outdoor fan motor unit 38 is detected from the normal DC bus voltage Vdc.

  At this time, when the voltage detection unit 81 detects that the DC bus voltage Vdc exceeds the first upper limit threshold voltage, the motor control unit 74 generates overvoltage on the DC bus lines 498 and 499 of the outdoor fan motor unit 38. It is determined that it has been done (step S9). Since it is ascertained that no overvoltage abnormality has occurred in the commercial power supply lines 48a and 48b before starting operation through steps S1 to S6, if it is detected in step S7 that an overvoltage has occurred, the outdoor fan motor The motor control unit 74 can determine that an overvoltage has occurred due to a malfunction such as a boosting operation caused by the operation of the unit 38 or the failure of the outdoor fan motor unit (inverter circuit or motor). In other words, it can be said that the abnormality of the power source and the abnormality of the fan motor unit can be separated.

  When it is detected in step S9 that the DC bus voltage Vdc exceeds the first upper limit threshold voltage, the motor control unit 74 causes the discharge control unit 746 to output the voltage abnormality signal Varm1 to the main body control unit 75 (step S10). In step S11, the discharge control unit 746 controls the discharge unit 497.

  When receiving the voltage abnormality signal Varm1, the main body control unit 75 transmits an abnormality notification signal indicating that an abnormality has occurred in the outdoor fan motor unit 38, for example. The indoor control unit 60 that has received the abnormality notification signal displays on the display unit 28 of the indoor unit 20 that an abnormality has occurred in the outdoor fan motor unit 38 (step S12), and returns to step S7.

  There are various types of control of the main body control unit 75 that has received the abnormal voltage signal Varm1, but for example, when the abnormal voltage signal Varm1 is continuously received even after a preset period, the main body control unit 75. May be configured to issue an instruction to end driving. If there is an instruction to end the operation, the motor control unit 74 recognizes that there is an instruction to end the operation in step S7, and the series of processing from step S1 to step S11 ends.

(5) Modification (5-1)
In the above embodiment, the voltage detection unit 81 determines whether or not an overvoltage has occurred in the commercial power supply lines 48a and 48b using the first upper limit threshold voltage (step S3), and uses the same first upper limit threshold voltage. It is also determined whether or not the DC bus voltage Vdc is an overvoltage (step S9).

  However, the threshold voltage for determining the overvoltage of the commercial power supply lines 48a and 48b may be different from the threshold voltage for determining the overvoltage of the DC bus voltage Vdc. For example, in step S9, the DC bus voltage Vdc is determined based on the first upper limit threshold voltage, and in step S3, the state of the commercial power supply lines 48a and 48b is determined based on the second upper limit threshold voltage that is higher than the first upper limit threshold voltage. May be. That is, in step S9, when the voltage detection unit 81 detects a voltage higher than the second upper limit threshold voltage, the motor control unit 74 may be configured to output the voltage abnormality signal Varm2 to the main body control unit 75. it can. Conversely, as the second threshold voltage for determining the state of the commercial power supply lines 48a and 48b, a voltage lower than the first upper limit threshold voltage for determining whether or not the DC bus voltage Vdc is an overvoltage may be used. .

(5-2)
In the above embodiment, whether or not an overvoltage has occurred in the commercial power supply lines 48a and 48b is determined in step S3 based on whether or not the voltage detection unit 81 exceeds the first upper limit threshold voltage. However, the determination to be performed by the motor control unit 74 in step S3 is not limited to determination of overvoltage.

  In step S2, the voltage detection unit 81 may be configured to detect whether or not the DC bus voltage Vdc is lower than the first lower limit threshold voltage (<first upper limit threshold voltage). In step S3, if the DC bus voltage Vdc is lower than the first lower limit threshold voltage, the motor control unit 74 determines that the commercial power supply lines 48a and 48b are undervoltage. In this case, a voltage abnormality signal different from the above-described voltage abnormality signals Varm1 and Varm2 is output from the motor control unit 74 to the main body control unit 75, and the main body control unit 75 causes the commercial power supply lines 48a and 48b to become undervoltage. It can be known that it has been detected.

  In the case of an undervoltage, unlike the case of an overvoltage, the inverter circuit 38b of the outdoor fan motor unit 38 and the like are less likely to be destroyed. Therefore, the interruption process from the commercial AC power supply in step S5 may be omitted.

  When the main body control unit 75 receives the voltage abnormality signal indicating the occurrence of the undervoltage, for example, the main body control unit 75 transmits an abnormality notification signal indicating that an abnormality has occurred in the commercial power supply lines 48 a and 48 b to the indoor control unit 60. Receiving the abnormality notification signal, the indoor control unit 60 displays on the display unit 28 of the indoor unit 20 that an abnormality has occurred in the commercial power supply lines 48a and 48b (step S6).

(5-3)
In the embodiment and the modified examples 5-1 and 5-2, in step S1, the outdoor fan motor unit 38 changes the outdoor fan motor 38a depending on whether or not there is an operation start instruction from the main body control unit 75 to the motor control unit 74. It is determined whether or not the rotation control is performed.

  However, the determination as to whether or not the outdoor fan motor unit 38 performs control to rotate the outdoor fan motor 38a can also be made based on whether or not there is an operation start instruction.

  For example, the control for stopping the motor can be determined based on the rotation speed measured by the rotation speed measurement unit 744 and the rotation speed command signal rd. That is, if the period during which the signal rm indicating the measured rotational speed and the rotational speed command signal rd are less than a predetermined rotational speed (for example, less than 100 rpm) continues for a predetermined period, control for stopping the motor is performed. If it is greater than or equal to a predetermined number of revolutions, it is determined that control for stopping the motor is not performed. That is, if the DC bus voltage Vdc detected by the voltage detector 81 when the signal rm indicating the measured rotational speed or the rotational speed command signal rd is less than the predetermined rotational speed indicates an overvoltage or an undervoltage, motor control is performed. The unit 74 may be configured to determine that an overvoltage or an undervoltage has occurred in the commercial power supply lines 48a and 48b. As described with reference to FIG. 3, the propeller fan 37 may be rotated by the external air flow, and when it is detected that the rotation speed measurement unit 744 does not rotate, such a propeller is used. Except for the case where the DC bus voltage Vdc changes due to rotation by the external force of the fan 37, it is possible to determine the voltage abnormality of the commercial power supply lines 48a and 48b.

(5-4)
In the embodiment and the modified examples 5-1 to 5-3, the motor control unit 74 determines whether or not a voltage abnormality has occurred in the commercial power supply lines 48a and 48b. The control unit 75 may perform this. For example, the detection result of the voltage detection unit 81 may be output from the discharge control unit 746 of the motor control unit 74 to the main body control unit 75 when the condition of step S1 is satisfied and the process proceeds to step S2. Good. For example, as shown in FIG. 8, in step S13 instead of step S3 in FIG. 7, the detection result is output from the discharge control unit 746 of the motor control unit 74 to the main body control unit 75 by the voltage detection unit 81. In the next step S14, the main body control unit 75 determines whether or not an overvoltage is supplied from the commercial power supply lines 48a and 48b based on the detection result of the voltage detection unit 81. Conventionally, if the main body control unit 75 has determined an overvoltage abnormality of the commercial power supply lines 48 a and 48 b from the voltage detection result, the main body control unit 75 thus uses the commercial power supply line based on the detection result of the voltage detection unit 81. By determining the overvoltage abnormality of 48a and 48b, it is possible to adopt a configuration almost similar to the conventional one. Similarly, instead of overvoltage abnormality of the commercial power supply lines 48a and 48b, or in parallel with the overvoltage abnormality, the main body control unit 75 may determine the abnormality of the undervoltage of the commercial power supply lines 48a and 48b.

(5-5)
In the above modified example 5-4, in step S2, the voltage detection unit 81 detects the overvoltage or the undervoltage of the commercial power supply lines 48a and 48b using the first upper limit threshold voltage and the first lower limit threshold voltage. However, the voltage detection unit 81 may output the voltage signal detected in step S2 as it is. Then, as shown in FIG. 9, the voltage signal Vv output from the voltage detection unit 81 at this time is output from the discharge control unit 746 of the motor control unit 74 to the main body control unit 75. The main body control unit 75 may determine the occurrence of overvoltage or undervoltage in the commercial power supply lines 48a and 48b based on the voltage signal Ev when the outdoor fan motor unit 38 is not driven.

  In particular, when motor vector control is performed or when output voltage correction is performed using a DC bus voltage, the motor control unit originally detects the voltage signal (absolute voltage value) to control the motor. Therefore, the signal can be used as it is.

(5-6)
In the above modified example 5-5 and the like, the main body control unit 75 causes the commercial power supply lines 48a and 48b to generate overvoltage and undervoltage based on the value of the DC bus voltage Vdc when the outdoor fan motor unit 38 is not driven. It is configured to judge. However, the event determined by the main body control unit 75 in step S14 is not limited to the occurrence of overvoltage or undervoltage in the commercial power supply lines 48a and 48b.

  As shown in FIG. 6, various actuators such as the four-way switching valve 32, the electric valve 34, and the compressor motor unit 40 are connected to the commercial power supply lines 48 a and 48 b. These abnormalities also change the voltages of the commercial power supply lines 48a and 48b, and the DC bus voltage Vdc changes due to the influence. Accordingly, in step S14, after confirming that no overvoltage or undervoltage has occurred in the commercial power supply lines 48a and 48b, the main body control unit is determined from the change in voltage generated in the DC bus voltage Vdc by operating these actuators. 75 may be configured to determine whether an abnormality has occurred in the actuator.

(5-7)
In the above embodiment, only the rectifier circuit 49B is separated by the electromagnetic contactor 90. However, as shown in FIG. 10, by separating all the subsequent stages of the control power supply (downstream side from the commercial power supply). Not only the outdoor fan motor unit but also the compressor motor unit and other actuators can be protected.

(5-8)
In the embodiment and the above-described modification, the air conditioner 10 in which the brushless DC motor is provided in the outdoor unit 30 is described as an example of the electric device including the motor. However, the indoor fan of the indoor unit 20 is described as an example. When a brushless DC motor is installed in the motor unit 23, the present invention can also be applied to the indoor fan motor unit 23. The electric device including the motor is not limited to the air conditioner 10 as in the above embodiment, and can be applied to other electric devices including a motor.

  For example, in an air conditioner configured to receive power from a commercial power source on the indoor unit side and supply power from the indoor unit to the outdoor unit, supply power to the outdoor unit when applied to the indoor fan motor unit. It is possible to protect the overvoltage from being applied to the outdoor unit by disconnecting.

For example, the air conditioner 10A shown in FIG. 11 receives power from the commercial AC power supply 48 by the indoor unit 20A and supplies power from the indoor unit 20A to the outdoor unit 30A. The indoor unit 20A includes an indoor control unit 60 , a control power supply 61 , an indoor fan motor unit 23 controlled by the indoor control unit 60, a wind direction adjusting mechanism 27, and a display unit 28. The indoor fan motor unit 23 includes an outdoor fan motor 38a, an inverter circuit 38b, a rectifier circuit 49B, a voltage detection unit 81, a current detection unit 82, a discharge unit 497, and a DC bus included in the outdoor fan motor unit 38 shown in FIG. The indoor fan motor 23a, the inverter circuit 23b, the rectifier circuit 49C, the voltage detection unit 81A, the current detection unit 82A, the discharge unit 497A, and the DC bus lines 498A and 499A corresponding to the lines 498 and 499 are provided. The indoor control unit 60 includes a main body control unit 65 and a motor control unit 64 corresponding to the main body control unit 75 and the motor control unit 74 included in the outdoor control unit 70.

  Similarly to the main body control unit 75 and the motor control unit 74, at least one of the motor control unit 64 and the main body control unit 65 is such that the DC bus voltage of the inverter circuit 23b satisfies an overvoltage or undervoltage condition and When the control state also satisfies a predetermined condition, it is determined that a voltage abnormality has occurred in the commercial power supply lines 48a and 48b to which the inverter circuit 23b is connected.

  When the main body control unit 65 determines that a voltage abnormality has occurred in the commercial power supply lines 48a and 48b, an overvoltage is applied to the outdoor unit 30 by disconnecting the power supply to the outdoor unit 30 by the electromagnetic contactor 91. Protects

(5-9)
In the above embodiment, the power supply voltage abnormality is described as an example. However, when there are a plurality of power supply systems having different voltages (in the example in Japan, 100V power supply and 200V power supply are mixed in the same room) ), It is also possible to detect an error (incorrect connection) in the power connection.

  When the power supply connection is incorrect as described above, the DC bus voltage value is significantly different from the normal connection value (for example, twice or 1/2 times the value) without operating any fan motor or actuator. Therefore, detection is easy. In particular, by providing a plurality of threshold values as described in the previous modification, the reliability of the state detection (detection of erroneous connection) can be increased.

(5-10)
The transmission of the abnormality signal / voltage signal to the main body control unit is not limited to the transmission means such as digital high / low signal, analog voltage signal, and state / voltage transmission by communication.

(5-11)
In the above-described embodiment and the above-described modified examples, the brushless DC motor has been described as an example of the motor included in the electric device. However, the motor included in the electric device is not limited to the brushless DC motor. In the above-described embodiment and the above-described modification, the commercial power supply lines 48a and 48b have been described as corresponding to one system of two-phase AC power supply. However, the commercial power supply line corresponds to a power supply of three or more phases. In addition, the present invention can be applied to an apparatus in which the air conditioner is connected to a plurality of commercial power supply lines.

(6) Features (6-1)
As described above, in the detection of the overvoltage or undervoltage of the DC bus voltage Vdc, the condition that the outdoor fan motor 38a is not driven or the outdoor fan motor 38a is not driven and controlled (the control for setting the stop state is not performed). (The predetermined condition of the control state) is added to detect the overvoltage or undervoltage of the DC bus voltage Vdc when there is no fluctuation of the DC bus voltage Vdc due to the driving of the outdoor fan motor 38a. Can do. This is because when the predetermined condition of the control state of the outdoor fan motor 38a is satisfied, the correlation between the change of the DC bus voltage Vdc and the change of the voltages of the commercial power supply lines 48a and 48b is strong. Thus, the voltage detection unit 81 for detecting the DC bus voltage Vdc supplied to the inverter circuit 38b can also serve as a detection device for detecting an overvoltage or an undervoltage of the commercial power supply line. By omitting the detection device, the number of detection devices for detecting an overvoltage or undervoltage can be reduced. Further, if the condition that the outdoor fan motor 38a is not driven or the condition that the outdoor fan motor 38a is not driven and controlled (the control is set to stop) is used, the outdoor fan motor 38a is driven. Since the influence can be eliminated, it is possible to improve the accuracy of determining the voltage abnormality of the commercial power supply lines 48a and 48b.

(6-2)
Conventionally, if the main body control unit 75 has received a signal indicating power supply abnormality from a detection device for detecting an overvoltage or undervoltage, the main body control unit 75 receives a voltage abnormality signal Varm2 indicating a power supply abnormality from the motor control unit 74. By receiving the signal, the configuration becomes the same as the conventional one, and the number of detection devices for detecting an overvoltage or an undervoltage can be reduced without changing the configuration of the main body control unit 75. Further, when the main body control unit 75 can be configured in the same manner as in the past, and it is not necessary to change the configuration of the main body control unit 75, an increase in the cost of the control device 50 can be suppressed.

(6-3)
In the case of the modification 5-5 described above, the condition that the DC bus voltage Vdc of the inverter circuit 38b satisfies the overvoltage or undervoltage condition and the outdoor fan motor 38a is not driven and controlled (the control state is a predetermined condition). ), The motor control unit 74 sends the voltage value Ev (voltage signal related to the DC bus voltage Vdc) detected by the voltage detection unit 81 to the main body control unit 75. Then, the main body control unit 75 determines the occurrence of a voltage abnormality in the commercial power supply line based on the voltage value Ev. Therefore, since the main body control unit 75 only needs to receive the voltage signal Vv from the motor control unit 74 in order to determine the voltage abnormality, detection for detecting an overvoltage or an undervoltage without increasing the number of terminals of the main body control unit 75. The number of devices can be reduced. Moreover, when the main body control part 75 can be comprised similarly to the past and the increase in the number of terminals of the main body control part 75 can be suppressed, the raise of the cost of the control apparatus 50 can be suppressed.

(6-4)
When it is determined by the electromagnetic contactor 90 shown in FIG. 6 that the voltage abnormality has occurred in the commercial power supply lines 48a and 48b, the main body control unit 75 performs the commercial power supply lines 48a and 48b and the DC bus line 498. , 499 is disconnected. As described above, when a voltage abnormality occurs in the commercial power supply lines 48a and 48b, the commercial power supply lines 48a and 48b are disconnected from the DC bus lines 498 and 499, thereby affecting the voltage abnormality of the commercial power supply lines 48a and 48b. Can be prevented from reaching the inverter circuit 38b for a long time, and the inverter circuit 38b can be prevented from failing due to a voltage abnormality in the commercial power supply lines 48a and 48b.

  Here, the main body control unit 75 uses the electromagnetic contactor 90 to cut off the connection between the commercial power supply lines 48 a and 48 b and the DC bus lines 498 and 499, but the motor control unit 74 uses the electromagnetic contactor 90. You may comprise so that it may interrupt | block.

(6-5)
As described in the above embodiment, at least one of the main body control unit 75 and the motor control unit 74 generates a voltage abnormality in the commercial power supply lines 48a and 48b based only on the DC bus voltage Vdc information of the inverter circuit 38b. Judge whether or not. In this case, since the main body control unit only receives information on the DC bus voltage Vdc from the motor control unit 74 in order to determine whether or not a voltage abnormality has occurred, information for detecting the voltage abnormality. Can be omitted. Thereby, the structure of the main body control part 75 is simplified and the cost concerning the control apparatus 50 can be reduced. In the above embodiment, it is determined whether or not a voltage abnormality has occurred in the commercial power supply lines 48a and 48b based only on the information on the DC bus voltage Vdc of the inverter circuit 38b. In order to improve, it can also comprise so that it may judge in consideration of other information.

(6-6)
As described in Modification 5-1 above, at least one of the motor control unit 74 and the main body control unit 75 determines whether or not to protect the inverter circuit 38b compared to the DC bus voltage Vdc. The determination is based on the threshold voltage (first threshold), and the voltage abnormality of the commercial power supply lines 48a and 48b is determined based on the second upper limit threshold voltage (second threshold) compared to the DC bus voltage Vdc. ing. As described above, the second upper limit threshold voltage is used to determine only the overvoltage abnormality of the commercial power supply lines 48a and 48b by having the second upper limit threshold voltage for determining the voltage abnormality of the commercial power supply lines 48a and 48b. Therefore, it is possible to improve the accuracy of the determination about the overvoltage abnormality of the commercial power supply lines 48a and 48b.

  In addition, although the case where the first lower limit threshold voltage is used to determine the occurrence of the undervoltage of the commercial power supply lines 48a and 48b is described in the modification example 5-2, it is the same as in the case of the above-described overvoltage detection. In addition, a second lower limit threshold voltage dedicated to detection of the undervoltage of the commercial power supply lines 48a and 48b may be provided. The effect of providing such a second lower limit threshold voltage is the case of providing the second upper limit threshold voltage. It is the same as the effect.

(6-7)
As described in Modification 5-6 above, the main body control unit 75 is configured to use information on the DC bus voltage Vdc of the inverter circuit 38b in order to determine whether an abnormality has occurred in the actuator. be able to. With this configuration, it is possible to omit a device for detecting information that can be confirmed by information obtained from the DC bus voltage Vdc of the inverter circuit 38b among information necessary for determining whether or not an abnormality has occurred in the actuator. it can.

DESCRIPTION OF SYMBOLS 10,10A Air conditioning apparatus 14 Refrigerant circuit 20, 20A Indoor unit 30, 30A Outdoor unit 31 Compressor 37 Propeller fan 38 Outdoor fan motor part 38a Outdoor fan motor 38b Inverter circuit 48 Commercial AC power supply 48a, 48b Commercial power supply line 50 Control device 60 indoor control unit 70 outdoor control unit 64, 74 motor control unit 65, 75 main body control unit 81, 81A voltage detection unit

Japanese Patent Laid-Open No. 5-114473

Claims (16)

A control device (50) for an electric device (10, 10A) including a motor (38a, 23a) to which driving power is supplied by an inverter circuit (38b, 23b),
Motor control units (74, 64) for controlling the motor;
A main body controller (75, 65) connected to the motor controller for controlling the electric device;
With
At least one of the motor control unit and the main body control unit is configured such that when the DC bus voltage of the inverter circuit satisfies an overvoltage or undervoltage condition and the control state of the motor also satisfies a predetermined condition, the inverter circuit It is determined that a voltage abnormality has occurred in the connected commercial power lines (48a, 8b) ,
At least one of the motor control unit and the main body control unit determines whether to protect the inverter circuit by comparing with the DC bus voltage based on the first upper limit threshold voltage and compares it with the DC bus voltage. The voltage abnormality of the commercial power line is determined based on the second upper limit threshold voltage, or it is determined based on the first lower limit threshold voltage whether the inverter circuit is to be protected by comparing with the DC bus voltage. And a control device that determines a voltage abnormality of the commercial power supply line based on a second lower threshold voltage as compared with a DC bus voltage . When the motor control unit determines that a voltage abnormality has occurred in the commercial power supply line, the motor control unit outputs a signal indicating the voltage abnormality of the commercial power supply line to the main body control unit.
The control device according to claim 1. The motor control unit sends a voltage signal related to a DC bus voltage to the main body control unit,
The main body control unit determines the occurrence of a voltage abnormality in the commercial power line based on a voltage signal related to a DC bus voltage.
The control device according to claim 1. The predetermined condition is that before the motor is driven or that the motor is controlled to be stopped.
The control device according to any one of claims 1 to 3. A DC bus (498, 499) connected to the inverter circuit and the commercial power line;
At least one of the motor control unit and the main body control unit disconnects the connection between the commercial power line and the DC bus when it is determined that a voltage abnormality has occurred in the commercial power line. ,
The control device according to any one of claims 1 to 4. At least one of the motor control unit and the main body control unit determines whether or not a voltage abnormality has occurred in the commercial power supply line based only on information on the DC bus voltage of the inverter circuit.
The control device according to any one of claims 1 to 5. A heat pump device (10) connected to a commercial power line (48a, 48b),
A fan motor (38a, 23a) for generating a flow of air exchanged with the refrigerant;
An inverter circuit (38b, 23b) connected to the commercial power line for supplying driving power to the fan motor;
A voltage detection unit (81, 81A) for detecting an abnormality by detecting a DC bus voltage of the inverter circuit;
A fan motor controller (74, 64) connected to the inverter circuit and the voltage detector for controlling the fan motor;
A main body control unit (75, 65) connected to the fan motor control unit for controlling the heat pump device;
An actuator (32, 34, 40, 27, 28) other than the fan motor driven by power supplied from the commercial power supply line in a system different from the DC bus voltage of the inverter circuit;
With
At least one of the fan motor control unit and the main body control unit is configured such that when the DC bus voltage of the inverter circuit satisfies an overvoltage or undervoltage condition and the control state of the fan motor also satisfies a predetermined condition, Judge that there is a voltage abnormality in the power line,
The main body control unit uses a DC bus voltage information of the inverter circuit to determine whether an abnormality has occurred in the actuator .   A heat pump device (10, 10A) connected to a commercial power line (48a, 48b),
  A fan motor (38a, 23a) for generating a flow of air exchanged with the refrigerant;
  An inverter circuit (38b, 23b) connected to the commercial power line for supplying driving power to the fan motor;
  A voltage detection unit (81, 81A) for detecting an abnormality by detecting a DC bus voltage of the inverter circuit;
  A fan motor controller (74, 64) connected to the inverter circuit and the voltage detector for controlling the fan motor;
  A main body control unit (75, 65) connected to the fan motor control unit for controlling the heat pump device;
  A control power supply (71, 61) functioning as a power supply for the main body control unit;
  An actuator (32, 34, 40, 27, 28) other than the fan motor driven by power supplied from the commercial power supply line in a system different from the DC bus voltage of the inverter circuit;
  A switch (90, 91) connected to the commercial power line and controlled by the main body control unit and capable of disconnecting at least one of the inverter circuit and the actuator from the commercial power line;
With
  At least one of the fan motor control unit and the main body control unit is configured such that when the DC bus voltage of the inverter circuit satisfies an overvoltage or undervoltage condition and the control state of the fan motor also satisfies a predetermined condition, Judge that there is a voltage abnormality in the power line,
  When the main body control unit determines that a voltage abnormality has occurred in the commercial power supply line, at least one of the inverter circuit and the actuator by the switch so as not to stop power supply to the control power supply. A heat pump device that disconnects one from the commercial power line.   The control power source is connected to the commercial power line in a system different from the DC bus voltage of the inverter circuit,
  The switch is connected to the commercial power line at a subsequent stage of connection to the control power source.
The heat pump device according to claim 8.   A heat pump device (10) connected to a commercial power line (48a, 48b),
  An indoor fan motor (23a) for generating a flow of air that exchanges heat with the refrigerant;
  An inverter circuit (23b) connected to the commercial power line for supplying driving power to the indoor fan motor;
  A voltage detector (81A) for detecting a DC bus voltage of the inverter circuit and detecting an abnormality;
  A fan motor controller (64) connected to the inverter circuit and the voltage detector for controlling the indoor fan motor;
  A main body control unit (65) connected to the fan motor control unit for controlling the heat pump device;
  An outdoor unit (30A) driven by electric power supplied from the commercial power line in a system different from the DC bus voltage of the inverter circuit;
  A switch (91) capable of disconnecting power supply from the commercial power line to the outdoor unit;
With
  At least one of the fan motor control unit and the main body control unit is configured such that when the DC bus voltage of the inverter circuit satisfies an overvoltage or undervoltage condition and the control state of the indoor fan motor also satisfies a predetermined condition, Judge that there is a voltage abnormality in the commercial power line,
  The main body control unit is a heat pump device that disconnects the outdoor unit from the commercial power line by the switch when it is determined that a voltage abnormality has occurred in the commercial power line. When the fan motor control unit determines that a voltage abnormality has occurred in the commercial power supply line, the fan motor control unit outputs a signal indicating the voltage abnormality of the commercial power supply line to the main body control unit.
The heat pump device according to any one of claims 7 to 10.   The fan motor control unit sends a voltage signal related to a DC bus voltage to the main body control unit,
  The main body control unit determines the occurrence of a voltage abnormality in the commercial power line based on a voltage signal related to a DC bus voltage.
The heat pump device according to any one of claims 7 to 11.   The predetermined condition is that before the fan motor is driven or the fan motor is controlled to be stopped.
The heat pump device according to any one of claims 7 to 12. A DC bus (498, 499) connected to the inverter circuit and the commercial power line;
  When at least one of the fan motor control unit and the main body control unit determines that a voltage abnormality has occurred in the commercial power supply line, the connection between the commercial power supply line and the DC bus is cut off. To
The heat pump device according to any one of claims 7 to 13. At least one of the fan motor control unit and the main body control unit determines whether or not a voltage abnormality has occurred in the commercial power supply line based only on the DC bus voltage information of the inverter circuit.
The heat pump device according to any one of claims 7 to 14. At least one of the fan motor control unit and the main body control unit determines whether to protect the inverter circuit by comparing with a DC bus voltage based on a first threshold value, and compares it with the DC bus voltage. Determining a voltage abnormality of the commercial power line based on a second threshold;
The heat pump device according to any one of claims 7 to 15.

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