JP6537594B2 - Air conditioner - Google Patents

Description

  The present invention relates to an air conditioner provided with a power supply device that drives a load device using power supplied from an external power supply.

  A conventional power supply device converts a DC voltage into an AC voltage when the DC voltage supplied from the DC power supply system is reduced, and boosts the converted AC voltage by outputting the AC voltage with a predetermined duty ratio. It is comprised so that the direct-current voltage required for control of these may be produced | generated (for example, refer patent document 1). According to this configuration, even if the direct current voltage supplied from the direct current feed system is lowered to a certain extent, it is possible to supply a desired direct current voltage to the load device.

  The power supply device of Patent Document 1 is provided in a load device, and a harmonic suppression circuit boosts a DC voltage supplied from a DC power supply system, and an isolated DC / DC converter converts the AC voltage to a power loss. By outputting with a duty ratio that minimizes the voltage, a DC voltage within the range of the rated voltage of the load device is generated.

JP, 2011-4505, A

  However, the power supply device of Patent Document 1 adopts a configuration in which a DC voltage required for the operation of the load device is generated using a booster circuit when the voltage of the DC power supply system drops, that is, the power supply device It is premised that the system can receive a certain amount of DC voltage. Here, the constant amount of DC voltage refers to a DC voltage that can generate a DC voltage within the range of the rated voltage of the load device by the boosting process. Therefore, when the DC voltage from the DC power supply system does not reach a certain amount, sufficient power can not be supplied to the load device, and there is a problem that the operation of the load device can not be continued.

  The present invention has been made to solve the problems as described above, and provides an air conditioner that allows the operation of the load device to continue even when the DC voltage supplied from the DC power supply system is reduced or stopped. With the goal.

An air conditioner according to the present invention comprises a refrigeration cycle in which a compressor, a condenser, a pressure reducing device, and an evaporator are sequentially connected by a refrigerant pipe, and a blower connected to at least one of the condenser and the evaporator. and a power supply for supplying power to at least one of the compressor and the blower as the load device, power supply, an inverter circuit for converting electric power supplied from the DC power supply or an AC power source to the driving power of the load device , A voltage detection unit that detects a DC voltage of the DC power supply, a power supply connection unit that connects the DC power supply and the inverter circuit, a DC voltage detected by the voltage detection unit, and whether the DC power supply is in a normal state The control unit that controls the operation of the power supply connection unit according to the magnitude relationship with the reference voltage, which is the determination reference, and switches the received power source of the power supply device; Electricity Less than in the case, power from the AC power supply controls the power connection to supply to the inverter circuit, when the DC voltage is equal to or higher than the reference voltage, the power source connected to power from the DC power is supplied to the inverter circuit Control the department .

  According to the present invention, since the power supply connection portion for connecting the DC power supply or the AC power supply to the inverter circuit according to the DC voltage of the DC power supply is used, the DC power supply and the AC power supply can be appropriately switched and used as a power reception power source. The operation of the load device can be continued even when the direct current voltage supplied from the direct current feed system is reduced or stopped.

It is a block diagram which shows schematic structure of the air conditioning apparatus which concerns on Embodiment 1 of this invention. It is the block diagram which illustrated the schematic structure of the air conditioning apparatus which has a fan attached to the condenser as a load device which the power supply device of FIG. 1 supplies electric power. It is the block diagram which illustrated the schematic structure of the air conditioning apparatus which has a fan attached to the evaporator as a load apparatus which the power supply apparatus of FIG. 1 supplies electric power. It is a flowchart which shows operation | movement of the air conditioning apparatus of FIGS. It is a block diagram which shows schematic structure of the air conditioning apparatus which concerns on Embodiment 2 of this invention. It is a block diagram which shows schematic structure of the air conditioning apparatus which concerns on Embodiment 3 of this invention. It is a flowchart which shows operation | movement of the air conditioning apparatus of FIG. It is a block diagram which shows schematic structure of the air conditioning apparatus which concerns on Embodiment 4 of this invention. It is a flowchart which shows operation | movement of the air conditioning apparatus of FIG.

First Embodiment
FIG. 1 is a block diagram showing a schematic configuration of an air conditioner according to Embodiment 1 of the present invention. As shown in FIG. 1, the air conditioner 91 includes a compressor 70 having a compressor motor 70a, a condenser 71, a pressure reducing device 72, and a refrigeration cycle 80 in which an evaporator 73 is sequentially connected by refrigerant piping, and a load And a power supply device 61 for supplying power to the compressor 70 as a device. In the refrigeration cycle 80, the compressor 70, the condenser 71, the pressure reducing device 72, and the evaporator 73 are sequentially connected by a refrigerant pipe, and the refrigerant is configured to circulate in the refrigerant pipe.

  The power supply device 61 includes an inverter circuit 10 for converting power supplied from the DC power supply (DC power supply system) 100 or AC power supply (commercial power supply) 200 into driving power for the compressor 70 as a load device; It has a smoothing and absorption circuit (inverter main circuit) 11 connected to the input side, and a power supply connection unit 21 for connecting the DC power supply 100 or the AC power supply 200 to the inverter circuit 10 according to the DC voltage of the DC power supply 100. ing. Further, the power supply device 61 detects a DC voltage of the DC power supply 100 and a control circuit 31 for controlling the operation of the power supply connection unit 21 and, for example, a rectifier circuit 40 connected to the AC power supply 200 at least. And a voltage detection unit 50.

  The smoothing and absorbing circuit 11 functions to absorb voltage fluctuations when connected to the DC power supply 100 via the power supply connection unit 21, and rectifies when it is connected to the AC power supply 200 via the power supply connection unit 21. It has a capacitor 11A that functions as a smoothing of the rectified waveform generated in the circuit 40. That is, the smoothing and absorbing circuit 11 absorbs voltage fluctuation of the DC voltage supplied from the DC power supply 100. The smoothing and absorbing circuit 11 smoothes the rectified waveform generated by the rectifying circuit 40 based on the AC voltage from the AC power supply 200. In addition, although the smooth absorption circuit 11 includes a protective circuit etc., it abbreviate | omits about description and description to each figure.

  The inverter circuit 10 converts the DC voltage input to the smoothing and absorption circuit 11 into an AC voltage. The inverter circuit 10 has a configuration in which, for example, six switching elements (not shown) are connected, and converts the DC voltage smoothed by the capacitor 11A into a three-phase AC voltage by the operation of each switching element. Then, the compressor 70 is supplied. The compressor 70 is driven by receiving the output voltage from the inverter circuit 10 to circulate the refrigerant. The inverter circuit 10 includes an inverter control unit (not shown) that outputs an AC voltage of a frequency proportional to the rotational speed of the compressor motor 70a by performing PWM control on each switching element.

  The power supply connection unit 21 switches the receiving power supply of the power supply device 61. Specifically, switching from the DC power supply 100 to the AC power supply 200 and switching from the AC power supply 200 to the DC power supply 100 are realized It is The power supply connection portion 21 is provided on the secondary side (output side) of the rectifier circuit 40, and is connected to the output end of the rectifier circuit 40 in the example of FIG.

  The rectifying circuit 40 in the first embodiment is provided to receive the AC power supply 200, and as shown in FIG. 1, six rectifying backflow prevention elements 40A are bridge-connected. The voltage detection unit 50 is always connected to the DC power supply 100, monitors the state of the DC voltage supplied from the DC power supply 100, and detects the DC voltage (DC voltage value) of the DC power supply 100. Further, the voltage detection unit 50 transmits the detected DC voltage to the control unit 31.

  The control unit 31 controls the operation of the power supply connection unit 21 according to the magnitude relationship between the DC voltage of the DC power supply 100 and the preset reference voltage, and the control unit 31 according to the result of determination by the state determination unit 31a. And a connection processing unit 31 b that controls the operation of the power supply connection unit 21 and adjusts the connection state between the received power supply and the power supply device 61. The state determination unit 31 a determines whether or not the connection switching process of the power supply connection unit 21 is necessary, and notifies the connection processing unit 31 b of the result of the determination. More specifically, the state determination unit 31a compares the DC voltage detected by the voltage detection unit 50 with the reference voltage to determine whether the DC power supply 100 is in a normal state.

  When the DC voltage detected by the voltage detection unit 50 is equal to or higher than the reference voltage, the state determination unit 31a notifies the connection processing unit 31b that the DC power supply 100 is in a normal state. Further, when the DC voltage detected by the voltage detection unit 50 is less than the reference voltage, the state determination unit 31a notifies the connection processing unit 31b that the DC power supply 100 is in an abnormal state. .

  The connection processing unit 31 b receives the notification from the state determination unit 31 a that the power from the DC power supply 100 is supplied to the inverter circuit 10 when notified that the DC power supply 100 is in the normal state. It is to control. Thus, the smoothing and absorbing circuit 11 is connected to the DC power supply 100 via the power supply connection unit 21. Further, when notified that the DC power supply 100 is in an abnormal state from the state determination unit 31a, the power supply connection unit 21 is controlled so that the power from the AC power supply 200 is supplied to the inverter circuit 10. Thus, the smoothing and absorbing circuit 11 is connected to the AC power supply 200 via the rectifier circuit 40 and the power supply connection unit 21.

  FIG. 2 is a block diagram illustrating a schematic configuration of an air conditioner 92 having a blower 75 provided side by side with the condenser 71 as a load device to which the power supply device 61 of FIG. 1 supplies power. As shown in FIG. 2, the air conditioner 92 includes a power supply device 61, a refrigeration cycle 80, and a blower 75 as a load device. The blower 75 has a fan motor 75a driven by the inverter circuit 10, and a fan 75b that rotates with the fan motor 75a as a power source and blows the air to the condenser 71.

  FIG. 3 is a block diagram illustrating a schematic configuration of an air conditioner 93 having a blower 76 provided side by side with the evaporator 73 as a load device to which the power supply device 61 of FIG. 1 supplies electric power. As shown in FIG. 3, the air conditioner 93 includes a power supply device 61, a refrigeration cycle 80, and a blower 76 as a load device. The blower 76 has a fan motor 76 a driven by the inverter circuit 10 and a fan 76 b that rotates with the fan motor 76 a as a power source and blows air to the evaporator 73.

  As shown in FIG.2 and FIG.3, the power supply device 61 can be applied also as a structure which drives the fan motor for heat exchangers which an air conditioning apparatus has. That is, the air conditioning apparatus according to the first embodiment may have at least one of the blower 75 provided to the condenser 71 and the blower 76 provided to the evaporator 73. Then, the power supply device 61 may be configured to execute drive control of at least one of the fan motors 75a and 76a in the same manner as in the case of the compressor motor 70a.

  Next, the operation of the air conditioners 91 to 93 will be described with reference to FIG. FIG. 4 is a flowchart showing the operation of the air conditioners 91-93.

  First, the voltage detection unit 50 detects a DC voltage supplied from the DC power supply 100, and transmits the detected DC voltage to the state determination unit 31a (FIG. 4: step S101). Next, the state determination unit 31a compares the DC voltage detected by the voltage detection unit 50 with a preset reference voltage to determine whether the DC power supply 100 is in a normal state (FIG. 4: Step S102).

  When the DC voltage detected by the voltage detection unit 50 is equal to or higher than the reference voltage (FIG. 4: step S102 / Yes), the state determination unit 31a notifies the connection processing unit 31b that the DC power supply 100 is in a normal state. It notifies (FIG. 4: step S103).

  The connection processing unit 31 b receives the notification from the state determination unit 31 a that the power from the DC power supply 100 is supplied to the inverter circuit 10 when notified that the DC power supply 100 is in the normal state. Control. That is, the connection processing unit 31 b controls the power supply connection unit 21 so that the DC power supply 100 is connected to the smoothing and absorption circuit 11, and causes the power supply device 61 to receive power from the DC power supply 100 (DC power reception state). When the connection processing unit 31 b places the power supply connecting unit 21 in a DC power receiving state, the DC voltage from the DC power supply 100 is directly supplied to the smoothing and absorbing circuit 11. The inverter circuit 10 converts the DC voltage supplied via the smoothing and absorption circuit 11 into a PWM voltage output of a frequency according to the refrigerant control of the air conditioning load, and outputs at least one of the load devices (the compressor 70, the blower 75, and the blower 76). Power) to drive the load device (FIG. 4: step S104).

  On the other hand, when the DC voltage detected by the voltage detection unit 50 is less than the reference voltage (FIG. 4: step S102 / No), the state determination unit 31a indicates that the DC power supply 100 is in an abnormal state. (FIG. 4: step S105).

  When notified that the DC power supply 100 is in an abnormal state from the state determination unit 31a, the connection processing unit 31b performs the power supply connection unit 21 so that the power from the AC power supply 200 is supplied to the inverter circuit 10. Control. That is, the connection processing unit 31 b controls the power supply connection unit 21 such that the AC power supply 200 is connected to the smoothing absorption circuit 11 via the rectification circuit 40, and the power supply 61 receives power from the AC power supply 200 (AC power supply Turn on the power). When connection processing unit 31b places power supply connection unit 21 in an AC power reception state, the AC voltage from AC power supply 200 is rectified by rectification circuit 40, smoothed by capacitor 11A, and supplied to inverter circuit 10 as a DC voltage. Ru. The inverter circuit 10 converts the DC voltage supplied via the smoothing and absorption circuit 11 into a PWM voltage output of a frequency according to the refrigerant control of the air conditioning load, and outputs at least one of the load devices (the compressor 70, the blower 75, and the blower 76). Power) to drive the load device (FIG. 4: step S106).

  The air conditioners 91 to 93 repeat the operations of steps S101 to S106 in FIG. 4 according to the direct current voltage of the direct current power source 100 detected constantly or at regular intervals. That is, the voltage detection unit 50 monitors the state of the DC power supply 100 constantly or at regular intervals, detects the DC voltage of the DC power supply 100, and transmits the detected DC voltage to the state determination unit 31a (FIG. 4: step) S101).

  When the direct-current voltage transmitted from the voltage detection unit 50 at all times or every fixed time is equal to or higher than the reference voltage (FIG. 4: step S102 / Yes), the state determination unit 31a determines that the direct-current power supply 100 is normal in the connection processing unit 31b. It notifies that it is a state (FIG. 4: step S103).

  When notified that the DC power supply 100 is in the normal state from the state determination unit 31a, the connection processing unit 31b performs the power supply connection unit 21 so that the power from the DC power supply 100 is supplied to the inverter circuit 10. Control. That is, connection processing unit 31 b receiving notification that DC power supply 100 is in a normal state from state determination unit 31 a is power supply connection unit 21 if power supply device 61 is in a state of receiving DC power supply 100. If the AC power supply 200 is receiving power, the state is switched to the DC power reception state. When the connection processing unit 31 b switches the power supply connection unit 21 to the DC power reception state, the DC voltage from the DC power supply 100 is directly supplied to the smoothing and absorbing circuit 11. The inverter circuit 10 converts the DC voltage supplied via the smoothing and absorption circuit 11 into a PWM voltage output of a frequency according to the refrigerant control of the air conditioning load, supplies power to the load device, and drives the load device (see FIG. 4: Step S104).

  On the other hand, when the direct-current voltage transmitted from the voltage detection unit 50 at any time or every fixed time is less than the reference voltage (FIG. 4: step S102 / No), the state determination unit 31a transmits the DC power 100 to the connection processing unit 31b It notifies that it is an abnormal state (FIG. 4: step S105).

  When notified that the DC power supply 100 is in an abnormal state from the state determination unit 31a, the connection processing unit 31b performs the power supply connection unit 21 so that the power from the AC power supply 200 is supplied to the inverter circuit 10. Control. In other words, connection processing unit 31 b receiving notification that DC power supply 100 is in an abnormal state from state determination unit 31 a is power supply connection unit 21 if power supply device 61 receives power from AC power supply 200. If the power is received from the DC power supply 100, the state is switched to the AC power reception state. When connection processing unit 31b switches power supply connection unit 21 to the AC power reception state, the AC voltage from AC power supply 200 is rectified by rectification circuit 40, smoothed by capacitor 11A, and supplied to inverter circuit 10 as DC voltage. Be done. The inverter circuit 10 converts the DC voltage supplied via the smoothing and absorption circuit 11 into a PWM voltage output of a frequency according to the refrigerant control of the air conditioning load, supplies power to the load device, and drives the load device (see FIG. 4: Step S106).

  The power supply device 61 according to the first embodiment adopts a configuration in which the power receiving unit is switched to the AC power supply 200 by the power connection portion 21 when the DC voltage of the DC power supply 100 falls below a predetermined value (reference voltage). Therefore, even when the DC voltage of the DC power supply 100 that constantly receives power is reduced, the operation of the air conditioners 91 to 93 can be continued. That is, since the air conditioners 91 to 93 are configured to switch from the DC power reception state to the AC power reception state when the DC voltage of the DC power source 100 constantly receiving power drops or stops, the operation of the load device Can be significantly continued. Therefore, according to the air conditioners 91 to 93, even when power feeding caused by a failure of the DC power feeding system is stopped, the AC voltage from the AC power source 200 can be received to maintain the operating state. .

  Further, in the air conditioners 91 to 93 according to the first embodiment, the power supply connection portion 21 is provided on the secondary side (output side) of the rectifier circuit 40, and receives power from the continuously connected DC power supply 100. Is configured not to pass through the rectifier circuit 40, it is possible to prevent the occurrence of loss in the rectifier circuit 40.

  Furthermore, in the air conditioners 91 to 93, when the DC voltage of the DC power supply 100 changes from a state less than the predetermined value to a state greater than or equal to the predetermined value, the state determination unit 31a generates the DC voltage transmitted from the voltage detection unit 50. Accordingly, connection processing unit 31b is notified that DC power supply 100 is in a normal state, and connection processing unit 31b is configured to switch power supply connection unit 21 to the DC power reception state in response to the notification. . Therefore, it is possible to reduce the loss in the rectifier circuit 40 which occurs in the AC power reception state.

  By the way, although the example in which the determination of whether or not the DC power supply 100 is in the normal state is performed in the above description is an example in which the state determination unit 31a in the control unit 31 performs the determination, components similar to the state determination unit 31a are It may be provided not in the control unit 31 but in the voltage detection unit 50. That is, the voltage detection unit 50 may determine whether the DC power supply 100 is in a normal state based on the detected DC voltage, and notify the control unit 31 of the result of the determination. In such a configuration, the voltage detection unit 50 determines that the state of the DC power supply 100 is normal when the detected DC voltage of the DC power supply 100 is equal to or higher than the reference voltage, and DC power when the DC voltage is less than the reference value. It is configured to determine that 100 is in an abnormal state. When the control unit 31 receives a notification from the voltage detection unit 50 that the state of the DC power supply 100 is normal, the control unit 31 controls the power supply connection unit 21 to be in the DC power reception state, and the DC power supply 100 When notified of the abnormal state, the power supply connection unit 21 may be controlled to be in the AC power reception state.

  Although FIG. 1 shows an example in which the rectifier circuit 40 is a three-phase rectifier corresponding to an AC power supply 200 composed of a three-phase AC power supply, a single-phase rectifier corresponding to a single phase AC power supply as the rectifier circuit 40 is shown. May be adopted. Moreover, although the structural example which converts a DC voltage into a three-phase alternating voltage was demonstrated as the inverter circuit 10 above, you may employ | adopt the structure which converts a DC voltage into a single phase alternating voltage as the inverter circuit 10. FIG.

Second Embodiment
Next, an air conditioning apparatus according to Embodiment 2 of the present invention will be described based on FIG. FIG. 5 is a block diagram showing a schematic configuration of the air conditioning apparatus 94 according to the second embodiment. The air conditioner 94 is characterized in that the power supply connection portion 22 is disposed not on the secondary side (output side) of the rectifier circuit 40 but on the primary side (input side). About the component equivalent to Embodiment 1 mentioned above, the description is abbreviate | omitted using the same code | symbol.

  As shown in FIG. 5, in the air conditioning apparatus 94, the power supply connection portion 22 is connected to the input end of the rectifier circuit 40. Therefore, the AC power supply 200 is connected to the rectifier circuit 40 via the power supply connection unit 22 under the control of the control unit 31. Further, in the air conditioner 94, the DC power supply 100 is connected to the input end of the rectifier circuit 40 via the power supply connection unit 22 under the control of the control unit 31.

  That is, the connection processing unit 31b receives the notification that the DC power supply 100 is in the normal state from the state determination unit 31a, the power supply connection unit 22 is connected such that the DC power supply 100 is connected to the input terminal of the rectifier circuit 40. Control. Thus, the power supplied from the DC power supply 100 is supplied to the inverter circuit 10 via the rectifier circuit 40 and the smoothing and absorbing circuit 11. Further, the connection processing unit 31 b receives the notification that the DC power supply 100 is in an abnormal state from the state determination unit 31 a, the power supply connection unit 22 is connected such that the AC power supply 200 is connected to the input terminal of the rectifier circuit 40. Control. Thus, the power supplied from the AC power supply 200 is supplied to the inverter circuit 10 via the rectifier circuit 40 and the smoothing and absorbing circuit 11. The other configuration and operation are similar to those of the first embodiment described above.

  In the air conditioning apparatus 94 according to the second embodiment, the power supply connection portion 22 is provided on the input side of the rectifier circuit 40. Therefore, when receiving power from the continuously connected direct current power supply 100, the direct current of the direct current power supply 100 is used. A voltage is supplied to the smoothing and absorbing circuit 11 through the rectifying circuit 40. Therefore, even when the polarities (positive and negative) of the DC power supply 100 are reversely connected, the rectification of the rectifier circuit 40 correctly adjusts the polarity of the DC voltage supplied to the smoothing and absorbing circuit 11. That is, according to the air conditioning apparatus 94, even when the polarity connection of the DC power supply 100 is wrong when connecting the power supply apparatus 62 to the DC power supply 100, the air conditioning apparatus 94 can be used without damaging each circuit. It can be driven. The other action and effect are the same as those of the first embodiment described above. That is, according to the air conditioning apparatus 94, the operation of the load device can be continued even when the DC voltage supplied from the DC power supply system is reduced or stopped.

Third Embodiment
Next, an air conditioning apparatus according to Embodiment 3 of the present invention will be described based on FIGS. 6 and 7. FIG. 6 is a block diagram showing a schematic configuration of the air conditioning apparatus 95 according to the third embodiment. The air conditioner 95 is characterized in that the drive output voltage required for driving the load device is adopted as a reference voltage which is a reference when determining whether the DC power supply 100 is normal. About the same component as Embodiment 1 and 2 mentioned above, the explanation is omitted using the same numerals.

  The control unit 32 in the power supply device 63 determines a frequency to be output to the compressor 70 as a load device according to the air conditioning load, and derives a drive voltage for deriving a load drive voltage required to drive the compressor 70 as a reference voltage. Drive determination unit 32 d that compares the load drive voltage derived in drive voltage deriving unit 32 c with the DC voltage detected in voltage detection unit 50 and determines whether or not the load device can be driven. And a connection processing unit 32 b that controls the operation of the power supply connection unit 21 according to the result of the determination by the drive determination unit 32 d.

  When the load drive voltage derived by drive voltage deriving unit 32c is less than the DC voltage detected by voltage detector 50 (the DC voltage of DC power supply 100 is equal to or higher than the reference voltage), drive determination unit 32d determines the load drive voltage. Since the data can be output to the compressor 70, the connection processing unit 32b is notified that driving of the load device is possible. When the load drive voltage derived by drive voltage deriving unit 32c is equal to or higher than the DC voltage detected by voltage detector 50 (when the DC voltage of DC power supply 100 is less than the reference voltage), drive determination unit 32d performs load drive. Since the voltage can not be output to the compressor 70, the connection processing unit 32b is notified that the load device can not be driven.

  Here, the drive determination unit 32 d determines whether or not the connection switching process of the power supply connection unit 21 is necessary, and notifies the connection processing unit 32 b of the result of the determination. The notification indicating that the load device can be driven and the notification that the load device can not be driven are determined by the drive determination unit 32d that the DC power supply 100 in the above-described state determination unit 31a of the first embodiment is in a normal state. This is the same signal as the notification of the effect and the notification that the DC power supply 100 is in an abnormal state. That is, connection processing unit 32b receives power notification from drive determination unit 32d that the load device can be driven, and power supply connection unit 21 is supplied with power from DC power supply 100 to inverter circuit 10. Control. Further, the connection processing unit 32b controls the power supply connection unit 21 so that the power from the AC power supply 200 is supplied to the inverter circuit 10 when receiving notification that the load device can not be driven from the drive determination unit 32d. It is a thing.

  Next, the operation of the air conditioner 95 will be described with reference to FIG. FIG. 7 is a flowchart showing the operation of the air conditioner 95.

  First, the voltage detection unit 50 detects a DC voltage supplied from the DC power supply 100, and transmits the detected DC voltage to the drive determination unit 32d (FIG. 7: step S201). Further, the drive voltage deriving unit 32c derives a load drive voltage required to drive the compressor 70 as a load device as a reference voltage, and transmits it to the drive determination unit 32d (FIG. 7: step S202).

  Next, the drive determination unit 32 d compares the load drive voltage derived in the drive voltage derivation unit 32 c with the DC voltage detected in the voltage detection unit 50. That is, the DC voltage of the DC power supply 100 is compared with the load drive voltage (FIG. 7: step S203).

  If the load drive voltage derived in drive voltage deriving unit 32 c is less than the DC voltage detected in voltage detection unit 50 (FIG. 7: step S 203 / Yes), drive determination unit 32 d can be connected to DC power supply 100 It is determined that the connection processing unit 32b determines that the driving of the load device is possible to the connection processing unit 32b (FIG. 7: step S204). The connection processing unit 32b controls the power supply connection unit 21 such that the smoothing and absorption circuit 11 is connected to the DC power supply 100 when receiving notification from the drive determination unit 32d that the load device can be driven. The power supply 63 is set to receive power from the DC power supply 100. Thereby, the power from the DC power supply 100 is supplied to the inverter circuit 10 (FIG. 7: step S205).

  On the other hand, when the load drive voltage derived in drive voltage deriving unit 32c is equal to or higher than the DC voltage detected by voltage detection unit 50 (the DC voltage of DC power supply 100 is less than the reference voltage) (FIG. 7: step S203 / No The drive determination unit 32d determines that the connection to the DC power supply 100 is not possible, and notifies the connection processing unit 32b that the load device can not be driven (FIG. 7: step S206). When notified that the load device can not be driven from the drive determination unit 32d, the connection processing unit 32b causes the power supply connection unit 21 to be connected to the AC power supply 200 via the rectification circuit 40. The power supply device 63 is controlled to receive power from the AC power supply 200. Thereby, the power from the AC power supply 200 is supplied to the inverter circuit 10 (FIG. 7: step S207).

  And the air conditioning apparatus 95 repeats the operation | movement of step S201-S207 of FIG. 7 according to the direct-current voltage of the direct-current power supply 100 detected regularly or for every fixed time. That is, the voltage detection unit 50 monitors the state of the DC power supply 100 constantly or at regular intervals, detects the DC voltage of the DC power supply 100, and transmits the detected DC voltage to the drive determination unit 32d (FIG. 7: step) S201). Further, the drive voltage deriving unit 32c derives a load drive voltage required for driving the compressor 70 as a load device, and transmits the load drive voltage to the drive determination unit 32d (FIG. 7: step S202).

  When the load drive voltage is less than the direct-current voltage transmitted from the voltage detection unit 50 at all times or every fixed time (FIG. 7: step S203 / Yes), the drive determination unit 32d drives the load device to the connection processing unit 32b. Is notified (FIG. 7: step S204). The connection processing unit 32b controls the power supply connection unit 21 so that the power from the DC power supply 100 is supplied to the inverter circuit 10 when receiving notification from the drive determination unit 32d that the load device can be driven. Do. That is, connection processing unit 32 b receiving notification from drive determination unit 32 d that the load device can be driven is connected to power supply connection unit 21 if power supply device 63 is in a state of receiving DC power supply 100. If the state is maintained and the AC power supply 200 is in a state of receiving power, the power supply connection unit 21 is switched to be in a state of receiving power from the DC power supply 100 (FIG. 7: step S205).

  On the other hand, when the load drive voltage is equal to or greater than the reference voltage when the DC voltage transmitted from the voltage detection unit 50 is constantly or every predetermined time (FIG. 7: step S203 / No), the drive determination unit 32d connects the connection processing unit 32b. Is notified that the load device can not be driven (FIG. 7: step S206). When receiving the notification that the load device can not be driven from the drive determination unit 32d, the connection processing unit 32b controls the power supply connection unit 21 so that the power from the AC power supply 200 is supplied to the inverter circuit 10. That is, if the connection processing unit 32b receives the notification that the load device can not be driven from the drive determination unit 32d, if the power supply device 63 is receiving power from the AC power supply 200, the connection processing unit 32b receives the state If it is maintained and receiving power from the DC power supply 100, the power supply connection unit 21 is switched to receive power from the AC power supply 200 (FIG. 7: step S207).

  As described above, in the third embodiment, since the load drive voltage derived according to the air conditioning load is adopted as the reference voltage, the control unit 32 executes the switching control of the power reception source according to the air conditioning load. can do. Therefore, when the load device can be driven, the DC power reception state can be maintained, and the loss generated in the rectifier circuit 40 in the AC power reception state can be reduced. The other action and effect are the same as those of the first embodiment described above. That is, according to the air conditioning apparatus 95, the operation of the load device can be continued even when the DC voltage supplied from the DC power supply system is reduced or stopped.

Fourth Embodiment
Next, an air conditioning apparatus according to Embodiment 4 of the present invention will be described based on FIGS. 8 and 9. FIG. 8 is a block diagram showing a schematic configuration of the air conditioning apparatus 96 according to the fourth embodiment. The air conditioner 96 is characterized in that the determination based on the drive output voltage required to drive the load device is performed after the determination based on the preset reference voltage. About the component same as Embodiment 1-3 mentioned above, description is abbreviate | omitted using the same code | symbol.

  The control unit 33 compares the DC voltage detected by the voltage detection unit 50 with a preset reference voltage to determine whether the DC power supply 100 is in a normal state or not, and the air conditioning The drive voltage deriving unit 33c determines the frequency to be output to the compressor 70 according to the load, and derives a load drive voltage required for driving the compressor 70 as a load device, and the load drive derived in the drive voltage derivation unit 33c. A result of determination by drive determination unit 33d that compares the voltage with a direct current voltage detected by voltage detection unit 50 to determine whether or not the load device can be driven, and state determination unit 33a or drive determination unit 33d And a connection processing unit 33 b that controls the operation of the power supply connection unit 21 according to the above.

  The state determination unit 33a has a function of transmitting a derivation command signal to the drive voltage derivation unit 33c when the DC voltage detected by the voltage detection unit 50 is less than the reference voltage. The drive voltage deriving unit 33c has a function of deriving the load drive voltage and transmitting it to the drive determining unit 33d when receiving the derived command signal from the state determining unit 33a.

  Next, the operation of the air conditioning apparatus 96 will be described with reference to FIG. FIG. 9 is a flowchart showing the operation of the air conditioner 96.

  First, the voltage detection unit 50 detects a DC voltage supplied from the DC power supply 100, and transmits the detected DC voltage to the state determination unit 33a (FIG. 9: step S301). Next, the state determination unit 33a compares the DC voltage detected by the voltage detection unit 50 with a reference voltage set in advance to determine whether the DC power supply 100 is in a normal state (FIG. 9: Step S302).

When the DC voltage detected by the voltage detection unit 50 is equal to or higher than the reference voltage (FIG. 9: step S302 / Yes), the state determination unit 33a notifies the connection processing unit 33b that the DC power supply 100 is in a normal state. (FIG. 9: step S303).
The connection processing unit 33b receiving the notification that the DC power supply 100 is in a normal state from the state determination unit 33a controls the power supply connection unit 21 so that the power from the DC power supply 100 is supplied to the inverter circuit 10, The power supply device 64 is set to receive power from the DC power supply 100. (FIG. 9: Step S304).

  On the other hand, when the DC voltage detected by the voltage detection unit 50 is less than the reference voltage (FIG. 9: step S302 / No), the state determination unit 33a transmits a derivation command signal to the drive voltage derivation unit 33c (FIG. 9: Step S305). The drive voltage derivation unit 33c that has received the derivation command signal from the state determination unit 33a derives the load drive voltage required to drive the compressor 70 from the state of the air conditioning load, and transmits it to the drive determination unit 33d (FIG. 9: step) S306).

  When the load drive voltage derived in drive voltage deriving unit 33 c is less than the DC voltage detected in voltage detector 50 (FIG. 9: step S 307 / Yes), drive determination unit 33 d sets compressor 70 for the load drive voltage. Can be output to the connection processing unit 33b to notify that the driving of the load device is possible (FIG. 9: step S308). The connection processing unit 33b receiving the notification that the load device can be driven from the drive determination unit 33d controls the power supply connection unit 21 so that the power from the DC power supply 100 is supplied to the inverter circuit 10, The device 64 receives power from the DC power supply 100 (FIG. 9: step S304).

When the load drive voltage derived by the drive voltage deriving unit 33c is equal to or higher than the DC voltage detected by the voltage detection unit 50 (FIG. 9: step S307 / No), the drive determination unit 33d performs the compressor 70 on the load drive voltage. Since it can not output to the connection processing unit 33b, the connection processing unit 33b is notified that the load device can not be driven (FIG. 9: step S309). The connection processing unit 33b that has received the notification that the load device can not be driven from the drive determination unit 33d controls the power supply connection unit 21 so that the power from the AC power supply 200 is supplied to the inverter circuit 10, and the power supply device 64 It is set as the state which receives electric power from AC power supply 200 (FIG. 9: step S310).

  In addition, the air conditioning apparatus 96 repeats the operations of steps S301 to S310 in FIG. 9 according to the direct current voltage of the direct current power supply 100 detected constantly or at regular intervals. That is, the voltage detection unit 50 monitors the state of the DC power supply 100 constantly or at regular intervals, detects the DC voltage of the DC power supply 100, and transmits the detected DC voltage to the state determination unit 33a (FIG. 9: step) S301). The control unit 33 executes the same control as the series of operation contents (steps S301 to S310). In step S304, if power supply 64 receives power from direct current power supply 100, connection processing unit 33b causes power supply connection unit 21 to maintain that state, and receives power from AC power supply 200. For example, the power supply connection unit 21 is switched to receive power from the DC power supply 100. In addition, in step S310, if connection processing unit 33b is in a state where power supply 64 receives power from AC power supply 200, connection processing unit 33b causes power supply connection unit 21 to maintain the state and receives power from DC power supply 100. If there is any, the power supply connection unit 21 is switched to receive power from the AC power supply 200.

  As described above, in the fourth embodiment, even when the DC voltage of DC power supply 100 is less than the reference voltage, the DC voltage of DC power supply 100 is greater than the load drive voltage derived according to the air conditioning load. If it is high, the DC power supply 100 continues the operation of the air conditioner 96. Therefore, when the air conditioning load is light, power can be supplied from the DC power supply 100 to the load device, and loss generated in the rectifier circuit 40 in the AC power reception state can be reduced. That is, with the configuration of the fourth embodiment, even when the DC voltage of DC power supply 100 falls below a predetermined value, when the air conditioning load is light, the operation of air conditioner 96 by DC power supply 100 is continued. can do.

  In addition, each embodiment mentioned above is a suitable specific example in a power supply device and an air conditioning apparatus, and the technical scope of the present invention is limited to these modes, unless there is a statement which limits the present invention in particular. It is not a thing. For example, in the second to fourth embodiments, an example in which the compressor 70 is applied as a load device is shown, but the air conditioners 94 to 96 are similar to FIGS. 2 and 3 illustrated in the first embodiment. As a load device, a fan motor for a heat exchanger is applied, and the operation of the fan motor can be continued even when the DC voltage supplied from the DC power supply system is reduced or stopped. Further, in the third and fourth embodiments, the configuration in which the power supply connection portion 21 is provided on the output side of the rectifier circuit 40 is illustrated, but the present invention is not limited to this configuration. That is, even if the air conditioner 95 or 96 is configured to have a power supply connection (for example, the power supply connection 22 shown in FIG. 5) connected to the input end of the rectifier circuit 40 instead of the power supply connection 21. Good.

  DESCRIPTION OF SYMBOLS 10 inverter circuit, 11 smoothing absorption circuit, 11A capacitor, 21, 22 power supply connection part 31, 32, 33 control part, 31a, 33a state determination part, 31b, 32b, 33b connection processing part, 32c, 33c drive voltage derivation | leading-out part , 32d, 33d drive determination unit, 40 rectification circuit, 40A rectification backflow prevention element, 50 voltage detection unit, 61 to 64 power supply device, 70 compressor (load device), 70a compressor motor, 71 condenser, 72 pressure reduction device , 73 evaporator, 75, 76 blower (load device), 75a, 76a fan motor, 75b, 76b fan, 80 refrigeration cycle, 91 to 96 air conditioner, 100 DC power supply (DC power supply system), 200 AC power supply (commercial Power supply).

Claims (6)

A refrigeration cycle in which a compressor, a condenser, a pressure reducing device, and an evaporator are sequentially connected by a refrigerant pipe;
A blower juxtaposed to at least one of the condenser and the evaporator;
A power supply device for supplying power to at least one of the compressor and the blower as a load device ;
The power supply device,
An inverter circuit that converts power supplied from a DC power supply or an AC power supply into driving power for the load device;
A voltage detection unit that detects a DC voltage of the DC power supply;
A power supply connection unit connecting the DC power supply and the inverter circuit;
The operation of the power supply connection unit is controlled according to the magnitude relationship between the DC voltage detected by the voltage detection unit and a reference voltage that is a determination reference of whether the DC power supply is in a normal state; And a control unit that switches the power reception device of the power supply device,
The control unit
If before Kijika current voltage is lower than the reference voltage, the control power supply connection portion so that the power from the AC power is supplied to the inverter circuit,
The air conditioning apparatus which controls the said power supply connection part so that the electric power from the said DC power supply may be supplied to the said inverter circuit, when the said DC voltage is more than the said reference voltage . The control unit
The air conditioner according to claim 1, wherein a load drive voltage required to drive the load device is derived as the reference voltage. The control unit
If before Kijika current voltage is lower than the reference voltage,
Derives the load drive voltage required for driving the load device, the derived the load drive voltage before Kijika current voltage or der lever, the power supply so that power from the AC power is supplied to the inverter circuit The air conditioner according to claim 1, wherein the connection is controlled. The control unit
If before Kijika current voltage is lower than the reference voltage,
If the derived the load driving voltage is less than the pre Kijika current voltage, the air conditioning apparatus according to claim 3, power from the DC power supply to control the power connection to supply to the inverter circuit. The power supply device
It further comprises a rectifier circuit connected to at least the AC power supply,
The power connection is:
The air conditioner according to any one of claims 1 to 4 , which is connected to an output end of the rectification circuit. The power supply device
It further comprises a rectifier circuit connected to at least the AC power supply,
The power connection is:
The air conditioning apparatus according to any one of claims 1 to 4 , which is connected to an input end of the rectification circuit.

Images