air conditioner

Abstract

The air conditioner (1) has an outdoor unit (2), which includes a three-phase AC power supply (21), a compressor (29) for compressing refrigerant, and an inverter circuit (30) for controlling the compressor (29). The outdoor unit (2) has a drive microcomputer (31) for driving the inverter circuit (30), a second diode bridge (34) connected to the inverter circuit (30), a first relay (36) configured on a first wiring (22), a second relay (37) configured on a third wiring (24), a surge resistor (38), and a third relay (39) connected to the first wiring (22) and the surge resistor (38). After the compressor (29) stops, the drive microcomputer (31) disconnects the first relay (36), the second relay (37), and the third relay (39).

Description

Technical Field

[0001] This disclosure relates to an air conditioner having an outdoor unit that includes a three-phase AC power supply, a frequency converter circuit, and a diode bridge. Background Technology

[0002] In existing air conditioners, multiple indoor units, remote controls, and a central controller are connected to the outdoor unit. During periods of inactivity, in order to maintain communication between the multiple indoor units, remote controls, and the central controller and the outdoor unit, power is supplied to the outdoor unit, and power is continuously supplied to the unused inverter circuit inside the outdoor unit (see, for example, Patent Document 1). The continuous supply of power to the inverter circuit is a factor contributing to increased power consumption during standby.

[0003] A circuit has been proposed that reduces power consumption from unused circuits by cutting off power to the outdoor unit during standby (see, for example, Patent Document 2).

[0004] Patent Document 1: Japanese Patent Application Publication No. 61-194944

[0005] Patent Document 2: International Publication No. 2018 / 011909

[0006] However, in air conditioners where multiple indoor units, remote controls, and a central controller are connected to the outdoor unit, the outdoor unit needs to constantly communicate with these multiple indoor units, remote controls, and the central controller, making it impossible to cut off power to the outdoor unit. Therefore, because the air conditioner consumes power even in standby mode, it continues to power unused inverter circuits and the microcomputer that drives the inverter circuits. Summary of the Invention

[0007] This disclosure was made in view of the above circumstances, and its purpose is to obtain an air conditioner that suppresses power consumption in standby mode.

[0008] To address the aforementioned issues and achieve the objective, the air conditioner disclosed herein comprises an outdoor unit, multiple indoor units connected to the outdoor unit, multiple remote controls, and a centralized controller for controlling the outdoor unit. Each of the multiple remote controls controls a corresponding indoor unit or outdoor unit among the multiple indoor units. The outdoor unit constantly communicates with the multiple indoor units, the multiple remote controls, and the centralized controller. The outdoor unit comprises: a three-phase AC power supply; a first diode bridge that rectifies the AC power output from the three-phase AC power supply into DC power; a compressor that compresses refrigerant; a control microcomputer that outputs instructions for controlling the compressor; and an inverter circuit that controls the compressor. The outdoor unit further comprises: a drive microcomputer that drives the inverter circuit; a switching power supply circuit that supplies the DC power rectified by the first diode bridge to the control microcomputer and the drive microcomputer; and a second diode bridge connected to the inverter circuit. The outdoor unit further includes: a first wiring corresponding to phase L1, connecting the three-phase AC power supply to a second diode bridge; a second wiring corresponding to phase L2, connecting the three-phase AC power supply to a second diode bridge; and a third wiring corresponding to phase L3, connecting the three-phase AC power supply to the second diode bridge. The outdoor unit further includes: a first relay disposed on the first wiring; a second relay disposed on the third wiring; a surge resistor connected to the side of the first relay closest to the second diode bridge to suppress surge current flowing when power is applied; and a third relay connected to the first wiring at a position closer to the three-phase AC power supply than the first relay, and to the surge resistor. After the compressor stops, the drive microcomputer disconnects the first, second, and third relays and cuts off the second diode bridge and the inverter circuit from the three-phase AC power supply. The outdoor unit further includes a power regulator that can switch the output of the drive microcomputer on or off. After the compressor stops, the control microcomputer stops the power regulator.

[0009] The air conditioner disclosed herein has the effect of suppressing power consumption during standby. Attached Figure Description

[0010] Figure 1 This is a diagram showing the structure of the air conditioner according to Embodiment 1.

[0011] Figure 2 This is a diagram showing the structure of the outdoor unit of the air conditioner in Embodiment 1.

[0012] Figure 3This is a flowchart showing the sequence of operations of the outdoor unit of the air conditioner in Embodiment 1.

[0013] Figure 4 This is a flowchart illustrating the sequence of operations of the outdoor unit of the air conditioner in Embodiment 2.

[0014] Figure 5 This is a diagram showing the structure of the outdoor unit of the air conditioner in Embodiment 3.

[0015] Figure 6 This is a flowchart illustrating the sequence of operations of the outdoor unit of the air conditioner in Embodiment 3.

[0016] Figure 7 This is a diagram showing the structure of the outdoor unit of the air conditioner in Embodiment 4.

[0017] Figure 8 This diagram shows the processor when a portion of each of the multiple remote controls of the air conditioner in Embodiment 1 is implemented by a processor.

[0018] Figure 9 This is a diagram showing the processing circuit when a portion of each of the multiple remote controls of the air conditioner in Embodiment 1 is implemented by a processing circuit. Detailed Implementation

[0019] The following is a detailed description of the air conditioner according to the embodiments, based on the accompanying drawings.

[0020] Implementation method 1.

[0021] Figure 1 This diagram illustrates the structure of an air conditioner 1 according to Embodiment 1. The air conditioner 1 includes an outdoor unit 2 and multiple indoor units 3 connected to the outdoor unit 2. Only one outdoor unit 2 exists in the air conditioner 1. Figure 1 The internal structure of outdoor unit 2 is also shown, but the internal structure of outdoor unit 2 will be discussed later. Figure 2 Please provide an explanation.

[0022] The air conditioner 1 also has multiple remote controls 4. Each remote control 4 is connected to a corresponding indoor unit 3 or outdoor unit 2 among the multiple indoor units 3, controlling the connected indoor unit 3 or outdoor unit 2. The air conditioner 1 also has a centralized controller 5 connected to the outdoor unit 2 to control the outdoor unit 2. The outdoor unit 2 constantly communicates with the multiple indoor units 3, the multiple remote controls 4, and the centralized controller 5.

[0023] Figure 2This diagram illustrates the structure of the outdoor unit 2 of the air conditioner 1 according to Embodiment 1. The outdoor unit 2 includes: a three-phase four-wire three-phase AC power supply 21; and a first wiring 22, a second wiring 23, a third wiring 24, and a fourth wiring 25 connected to the three-phase AC power supply 21. The first wiring 22 corresponds to L1, the second wiring 23 corresponds to L2, the third wiring 24 corresponds to L3, and the fourth wiring 25 corresponds to the neutral wire. Each of the L1, L2, and L3 phases is a single-phase AC phase in the three-phase AC system, and each phase is different from the other two phases of the three-phase AC system.

[0024] The outdoor unit 2 also includes a first diode bridge 26 that rectifies the AC power output from the three-phase AC power supply 21 into DC power, a switching power supply circuit 27, and a path 28 for supplying the DC power rectified by the first diode bridge 26 to the switching power supply circuit 27. A second wiring 23 and a fourth wiring 25 are connected to the first diode bridge 26.

[0025] The outdoor unit 2 also includes a compressor 29 for compressing refrigerant, an inverter circuit 30 for controlling the compressor 29, and a drive microcomputer 31 for driving the inverter circuit 30. The outdoor unit 2 also includes a power regulator 32 and a control microcomputer 33 for controlling the power regulator 32. The power regulator 32 has the function of switching the output of the drive microcomputer 31 on and off.

[0026] The switching power supply circuit 27 supplies DC power, rectified by the first diode bridge 26, to the control microcomputer 33. According to the control of the control microcomputer 33, the switching power supply circuit 27 supplies DC power to the drive microcomputer 31 via the power regulator 32. Alternatively, the switching power supply circuit 27 can also be independent of the control microcomputer 33. The drive microcomputer 31 drives the inverter circuit 30 based on the supplied DC power. That is, the control microcomputer 33 outputs instructions for controlling the compressor 29. Although in Figure 1 and Figure 2 The outdoor unit 2 is not shown, but it has a fan motor, and the control microcomputer 33 also outputs instructions for controlling the fan motor.

[0027] The outdoor unit 2 also includes a second diode bridge 34 connected on one side to a three-phase AC power supply 21 via a first wiring 22, a second wiring 23, and a third wiring 24, and a smoothing capacitor 35 connected to the other side of the second diode bridge 34. The inverter circuit 30 is connected to the smoothing capacitor 35. Furthermore, the second diode bridge 34 is connected to the inverter circuit 30 via the smoothing capacitor 35.

[0028] The outdoor unit 2 also includes a first relay 36 configured to connect the three-phase AC power supply 21 to the second diode bridge 34 via a first wiring 22, and a second relay 37 configured to connect the three-phase AC power supply 21 to the second diode bridge 34 via a third wiring 24. The second wiring 23, like the first wiring 22 and the third wiring 24, connects the three-phase AC power supply 21 to the second diode bridge 34. The connection states of the second diode bridge 34 and the inverter circuit 30 to the three-phase AC power supply 21 are determined by the on and off states of the first relay 36 and the second relay 37.

[0029] The outdoor unit 2 also includes a surge resistor 38, which suppresses the surge current flowing through the smoothing capacitor 35 for charging when the first relay 36 is turned on. That is, the surge resistor 38 suppresses the surge current flowing when power is applied. The surge resistor 38 is connected to the side of the first relay 36 closest to the second diode bridge 34. The outdoor unit 2 also includes a third relay 39, which is connected to the surge resistor 38 in the first wiring 22 on the side closer to the three-phase AC power supply 21 than the first relay 36. To prevent power to the inverter circuit 30 when the first relay 36 and the second relay 37 are off, the surge resistor 38 is switched on and off via the third relay 39.

[0030] Next, the operation of outdoor unit 2 will be explained. Figure 3 This is a flowchart illustrating the sequence of operations of the outdoor unit 2 of the air conditioner 1 in Embodiment 1. When the air conditioner 1 stops operating, the control microcomputer 33 receives an operation stop command (S1) and stops the inverter circuit 30 (S2). The drive microcomputer 31 then disconnects the first relay 36, the second relay 37, and the third relay 39 (S3).

[0031] Furthermore, after the outdoor unit 2 stops operating and the compressor 29 stops, the control microcomputer 33 outputs an instruction to the drive microcomputer 31 to disconnect the first relay 36, the second relay 37, and the third relay 39. Based on this instruction, the drive microcomputer 31 disconnects the first relay 36, the second relay 37, and the third relay 39, thereby disconnecting the second diode bridge 34 and the inverter circuit 30 from the three-phase AC power supply 21.

[0032] As described above, since the unused second diode bridge 34 and inverter circuit 30 are disconnected from the three-phase AC power supply 21 during standby when the compressor 29 is not driven, the air conditioner 1 of Embodiment 1 can suppress the power consumed by the second diode bridge 34 and inverter circuit 30 during standby. That is, the air conditioner 1 can suppress power consumption during standby.

[0033] Implementation method 2.

[0034] The structure of the air conditioner in Embodiment 2 is the same as that of the air conditioner 1 in Embodiment 1. However, a portion of the operation of the air conditioner in Embodiment 2 differs from that of the air conditioner 1. In Embodiment 2, the differences from Embodiment 1 will be explained.

[0035] Figure 4 This is a flowchart illustrating the sequence of operations of the outdoor unit 2 of the air conditioner in Embodiment 2. When the air conditioner stops operating, the control microcomputer 33 receives an operation stop command (S11) and stops the inverter circuit 30 (S12). The drive microcomputer 31 disconnects the first relay 36, the second relay 37, and the third relay 39 (S13). The control microcomputer 33 stops the power regulator 32 (S14). The drive microcomputer 31 stops operating (S15).

[0036] That is, in Embodiment 2, after the compressor 29 stops, the operations from steps S1 to S3 described in Embodiment 1 are performed, and then the control microcomputer 33 stops the power regulator 32. As described in Embodiment 1, the switching power supply circuit 27 supplies DC power to the drive microcomputer 31 via the power regulator 32 according to the control performed by the control microcomputer 33.

[0037] In Embodiment 2, since the control microcomputer 33 stops the power regulator 32 after the compressor 29 stops, DC power is not supplied to the drive microcomputer 31 that drives the inverter circuit 30. That is, the air conditioner of Embodiment 2 can suppress not only the power consumed by the second diode bridge 34 and the inverter circuit 30 in standby mode, but also the power consumed by the drive microcomputer 31.

[0038] Implementation method 3.

[0039] Figure 5 This diagram illustrates the structure of the outdoor unit 2A in the air conditioner of Embodiment 3. In Embodiment 3, the outdoor unit 2A replaces the outdoor unit 2 of the air conditioner 1 in Embodiment 1. The only difference between Embodiment 3 and Embodiment 1 is that the outdoor unit 2 of Embodiment 1 is replaced by outdoor unit 2A. In Embodiment 3, the differences from Embodiment 1 will be primarily explained.

[0040] Outdoor unit 2A has all the components of outdoor unit 2. Outdoor unit 2A also has a first reactor 40 located in the first wiring 22 on the side of the three-phase AC power supply 21 connected to the third relay 39, a second reactor 41 located in the second wiring 23, and a third reactor 42 located in the third wiring 24 on the side of the three-phase AC power supply 21 connected to the second relay 37.

[0041] The outdoor unit 2A also includes a power factor improvement circuit 43. The power factor improvement circuit 43 comprises a first insulated-gate bipolar transistor 44, a third diode bridge 45 connected to the first insulated-gate bipolar transistor 44, a resonant capacitor 46 connected to the third diode bridge 45, and a power factor improvement circuit drive microcomputer 47 that drives the first insulated-gate bipolar transistor 44. One end of the third diode bridge 45 is connected between the first reactor 40 of the first wiring 22 and the location where the third relay 39 is connected. The resonant capacitor 46 is also connected to the inverter circuit 30. The power factor improvement circuit drive microcomputer 47 is connected to the drive microcomputer 31.

[0042] The power factor improvement circuit 43 also includes a second insulated-gate bipolar transistor 48 and a fourth diode bridge 49 connected to the second insulated-gate bipolar transistor 48. One end of the fourth diode bridge 49 is connected between the second reactor 41 and the second diode bridge 34 of the second wiring 23. The fourth diode bridge 49 is also connected to a resonant capacitor 46. The microcomputer 47 driving the power factor improvement circuit also drives the second insulated-gate bipolar transistor 48.

[0043] The power factor improvement circuit 43 also includes a third insulated-gate bipolar transistor 50 and a fifth diode bridge 51 connected to the third insulated-gate bipolar transistor 50. One end of the fifth diode bridge 51 is connected between the third reactor 42 of the third wiring 24 and the second relay 37. The fifth diode bridge 51 is also connected to the resonant capacitor 46. The microcomputer 47 driving the power factor improvement circuit also drives the third insulated-gate bipolar transistor 50.

[0044] Power is supplied to the power factor improvement circuit drive microcomputer 47 via the power regulator 32 and the drive microcomputer 31. If the control microcomputer 33 stops the output of the power regulator 32, the power supply to the drive microcomputer 31 and the power factor improvement circuit drive microcomputer 47 is stopped.

[0045] Figure 6This is a flowchart illustrating the sequence of operations of the outdoor unit 2A of the air conditioner in Embodiment 3. When the air conditioner stops operating, the control microcomputer 33 receives an operation stop command (S21) and stops the inverter circuit 30 (S22). The drive microcomputer 31 disconnects the first relay 36, the second relay 37, and the third relay 39 (S23). The control microcomputer 33 stops the power regulator 32 (S24). The drive microcomputer 31 and the power factor correction circuit drive microcomputer 47 stop operating (S25).

[0046] That is, in Embodiment 3, after the compressor 29 stops, the operations from steps S1 to S3 described in Embodiment 1 are performed, and then the control microcomputer 33 stops the power regulator 32. The switching power supply circuit 27 supplies DC power to the drive microcomputer 31 and the power factor improvement circuit drive microcomputer 47 via the power regulator 32, whose output can be stopped by the control microcomputer 33, according to the control performed by the control microcomputer 33. As described above, the switching power supply circuit 27 may also be independent of the control microcomputer 33.

[0047] In embodiment 3, since the control microcomputer 33 stops the power regulator 32 after the compressor 29 stops, DC power is not supplied to the drive microcomputer 31 that drives the inverter circuit 30. DC power is also not supplied to the power factor improvement circuit drive microcomputer 47 that drives the first insulated-gate bipolar transistor 44, the second insulated-gate bipolar transistor 48, and the third insulated-gate bipolar transistor 50 included in the power factor improvement circuit 43.

[0048] Therefore, the air conditioner of Embodiment 3 can suppress not only the power consumed by the second diode bridge 34 and the inverter circuit 30 in standby mode, but also the power consumed by the drive microcomputer 31 and the power factor improvement circuit drive microcomputer 47. Furthermore, the air conditioner of Embodiment 3 can suppress standby power consumption even when the power factor improvement circuit 43 is present.

[0049] Implementation method 4.

[0050] Figure 7 This diagram illustrates the structure of the outdoor unit 2B in the air conditioner of Embodiment 4. In Embodiment 4, the outdoor unit 2B replaces the outdoor unit 2A of the air conditioner of Embodiment 3. The only difference between Embodiment 4 and Embodiment 3 is that the outdoor unit 2A of Embodiment 3 is replaced by the outdoor unit 2B. In Embodiment 4, the differences from Embodiment 3 will be primarily explained.

[0051] Outdoor unit 2B has all the components of outdoor unit 2A. The connection positions of the power factor improvement circuit 43 to the first wiring 22, the second wiring 23, and the third wiring 24 differ between outdoor unit 2B in embodiment 4 and outdoor unit 2A in embodiment 3. Specifically, in outdoor unit 2B, one end of the third diode bridge 45 is connected between the location on the first wiring 22 where the surge-resistant resistor 38 is connected and the location on the second diode bridge 34.

[0052] One end of the fourth diode bridge 49 is connected between the second reactor 41 and the second diode bridge 34 of the second wiring 23. One end of the fifth diode bridge 51 is connected between the second relay 37 and the second diode bridge 34 of the third wiring 24.

[0053] In Embodiment 4, after the compressor 29 stops, the operations from steps S1 to S3 described in Embodiment 1 are performed, and then the control microcomputer 33 stops the power regulator 32. Therefore, DC power is not supplied to the drive microcomputer 31 that drives the inverter circuit 30. DC power is also not supplied to the power factor improvement circuit drive microcomputer 47 that drives the first insulated-gate bipolar transistor 44, the second insulated-gate bipolar transistor 48, and the third insulated-gate bipolar transistor 50 included in the power factor improvement circuit 43.

[0054] Therefore, the air conditioner of embodiment 4 can suppress not only the power consumed by the second diode bridge 34 and the inverter circuit 30 in standby mode, but also the power consumed by the drive microcomputer 31 and the power factor improvement circuit drive microcomputer 47.

[0055] Figure 8 This diagram illustrates the processor 81 in the case where a portion of each of the multiple remote controls 4 in the air conditioner 1 of Embodiment 1 is implemented by the processor 81. That is, a portion of the function of each of the multiple remote controls 4 can also be implemented by the processor 81 that executes a program stored in the memory 82.

[0056] Processor 81 is a CPU (Central Processing Unit), processing unit, arithmetic unit, microprocessor, or DSP (Digital Signal Processor). Figure 8 The memory 82 is also shown in the image.

[0057] In cases where a portion of the functions of each of the multiple remote controllers 4 is implemented by the processor 81, this portion of the function is implemented by the processor 81 in conjunction with software, firmware, or a combination of software and firmware. The software or firmware is described as a program and stored in the memory 82. The processor 81 implements the portion of the functions of each of the multiple remote controllers 4 by reading and executing the program stored in the memory 82.

[0058] In cases where a portion of the functionality of each of the multiple remote controllers 4 is implemented by the processor 81, each of the multiple remote controllers 4 has a memory 82 for storing a program that causes at least a portion of the steps performed by each of the multiple remote controllers 4 to be executed as a result. The program stored in the memory 82 can also be described as a program that causes the computer to execute a portion of each of the multiple remote controllers 4.

[0059] The memory 82 includes, for example, non-volatile or volatile semiconductor memories such as RAM (Random Access Memory), ROM (Read Only Memory), flash memory, EPROM (Erasable Programmable Read Only Memory), EEPROM (Electrically Erasable Programmable Read-Only Memory), magnetic disks, floppy disks, optical disks, compressed optical disks, mini-CDs, or DVDs (Digital Versatile Disk).

[0060] Figure 9 This diagram illustrates the processing circuit 91 in the case where a portion of each of the multiple remote controls 4 in the air conditioner 1 of Embodiment 1 is implemented by the processing circuit 91. That is, a portion of each of the multiple remote controls 4 can also be implemented by the processing circuit 91.

[0061] The processing circuit 91 is dedicated hardware. The processing circuit 91 may be, for example, a single circuit, a composite circuit, a programmable processor, a parallel programmable processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a combination thereof.

[0062] Each part of the multiple remote controllers 4 can also be implemented using dedicated hardware separate from the rest.

[0063] For the multiple functions of each of the multiple remote controllers 4, some of these functions can be implemented by software or firmware, while the remaining functions can be implemented by dedicated hardware. In this way, the multiple functions of each of the multiple remote controllers 4 can be implemented through hardware, software, firmware, or a combination thereof.

[0064] The central controller 5 of the air conditioner 1 in Embodiment 1 can be implemented by a processor or by a processing circuit. The processor is the same as the processor 81 described above. The processing circuit is the same as the processing circuit 91 described above.

[0065] The structure shown in the above embodiments is an example and can be combined with other known technologies, or the embodiments can be combined with each other, or a part of the structure can be omitted or changed without departing from the spirit.

[0066] Explanation of reference numerals in the attached figures:

[0067] 1…Air conditioner; 2, 2A, 2B…Outdoor unit; 3…Indoor unit; 4…Remote control; 5…Central controller; 21…Three-phase AC power supply; 22…First wiring; 23…Second wiring; 24…Third wiring; 25…Fourth wiring; 26…First diode bridge; 27…Switching power supply circuit; 28…Path; 29…Compressor; 30…Inverter circuit; 31…Drive microcomputer; 32…Power regulator; 33…Control microcomputer; 34…Second diode bridge; 35…Smoothing capacitor; 36…First relay; 37…Second… Relay; 38… Surge-resistant resistor; 39… Third relay; 40… First reactor; 41… Second reactor; 42… Third reactor; 43… Power factor improvement circuit; 44… First insulated-gate bipolar transistor; 45… Third diode bridge; 46… Resonant capacitor; 47… Microcomputer for driving power factor improvement circuit; 48… Second insulated-gate bipolar transistor; 49… Fourth diode bridge; 50… Third insulated-gate bipolar transistor; 51… Fifth diode bridge; 81… Processor; 82… Memory; 91… Processing circuit.

Claims

1. An air conditioner characterized by comprising: Possessing: an outdoor unit; a plurality of indoor units connected to the outdoor unit; a plurality of remote controllers; and a centralized controller that controls the outdoor unit, the plurality of remote controllers each controls the outdoor unit or a corresponding indoor unit among the plurality of indoor units, the outdoor unit is always in communication with the centralized controller, the plurality of indoor units, and the plurality of remote controllers, the outdoor unit has: a three-phase AC power source; a first diode bridge that rectifies AC power output from the three-phase AC power source to DC power; a compressor that compresses refrigerant; a control microcomputer that outputs instructions for controlling the compressor; an inverter circuit that controls the compressor; a drive microcomputer that drives the inverter circuit; a switching power supply circuit that supplies DC power rectified by the first diode bridge to the control microcomputer and the drive microcomputer; a second diode bridge connected to the inverter circuit; a first wiring that connects the three-phase AC power source and the second diode bridge corresponding to an L1 phase; a second wiring that connects the three-phase AC power source and the second diode bridge corresponding to an L2 phase; a third wiring that connects the three-phase AC power source and the second diode bridge corresponding to an L3 phase; a first relay disposed on the first wiring; a second relay disposed on the third wiring; a surge resistance connected to the first relay on a side closer to the second diode bridge to suppress a surge current that flows when power is applied; a third relay connected to the first wiring on a side closer to the three-phase AC power source than the first relay and the surge resistance; a first reactor disposed on the first wiring on a side closer to the three-phase AC power source than a position at which the third relay is connected; a second reactor disposed on the second wiring; a third reactor disposed on the third wiring on a side closer to the three-phase AC power source than the second relay; and a power factor improvement circuit, the power factor improvement circuit has: a first insulated gate bipolar transistor; a third diode bridge connected to the first insulated gate bipolar transistor; a second insulated gate bipolar transistor; a fourth diode bridge connected to the second insulated gate bipolar transistor; a third insulated gate bipolar transistor; a fifth diode bridge connected to the third insulated gate bipolar transistor; a resonance capacitor connected to the third diode bridge, the fourth diode bridge, the fifth diode bridge, and the inverter circuit; and a power factor improvement circuit drive microcomputer that drives the first insulated gate bipolar transistor, the second insulated gate bipolar transistor, and the third insulated gate bipolar transistor, ​ After the compressor is stopped, the drive microcomputer brings the first relay, the second relay, and the third relay into an off state, and cuts off the second diode bridge and the inverter circuit from the three-phase AC power supply, The outdoor unit further has a power supply regulator having a function of being able to switch the output of the drive microcomputer to on or off, After the compressor is stopped, the control microcomputer stops the power supply regulator.

2. The air conditioner according to claim 1, wherein one end of the third diode bridge is connected to a position of the first wiring between the first reactor and a position at which the third relay is connected, one end of the fourth diode bridge is connected to a position of the second wiring between the second reactor and the second diode bridge, one end of the fifth diode bridge is connected to a position of the third wiring between the third reactor and the second relay, the power factor improvement circuit drive microcomputer is supplied with power via the power supply regulator, After the compressor is stopped, the control microcomputer stops the power supply regulator.

3. The air conditioner according to claim 1, wherein one end of the third diode bridge is connected to a position of the first wiring between a position at which the surge resistance is connected and the second diode bridge, one end of the fourth diode bridge is connected to a position of the second wiring between the second reactor and the second diode bridge, one end of the fifth diode bridge is connected to a position of the third wiring between the second relay and the second diode bridge, the power factor improvement circuit drive microcomputer is supplied with power via the power supply regulator, After the compressor is stopped, the control microcomputer stops the power supply regulator.

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