JP2017203594A - Air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air conditioner capable of suppressing fluctuation of a room temperature as much as possible when switching a power supply from an AC power supply to a DC power supply.SOLUTION: In an air conditioner 50, a power supply circuit 20 is connected to an AC power supply and a DC power supply, and drives a compressor 84 based only on one power supply out of the AC power supply and the DC power supply. A control part 89 controls the power supply circuit 20 in such a manner that the compressor 84 is started based on the AC power supply, and when a predetermined switching condition is satisfied, the compressor 84 is stopped temporarily, and then, the compressor 84 is restarted based on the DC power supply. The switching condition includes the condition that predetermined first time T has elapsed since a room temperature has reached a temperature range according to a preset temperature.SELECTED DRAWING: Figure 3

Description

  This disclosure relates to a heat pump type air conditioner, and is particularly suitable for an air conditioner that can use both a DC power source such as a storage battery and a commercial AC power source as drive power sources.

  Conventionally, a technique for driving a compressor of an air conditioner (also referred to as an “air conditioner”) using a DC power supply and a commercial AC power supply in combination has been proposed.

  For example, Japanese Patent Laid-Open No. 2001-65927 (Patent Document 1) discloses an air conditioner using a commercial AC power source and a storage battery as power sources. In the air conditioner of this document, an AC voltage from a commercial AC power source is converted into a DC voltage by a rectifying / smoothing circuit, and a DC voltage from a storage battery is boosted by a bidirectional converter. Then, the DC voltage output from the rectifying / smoothing circuit and the DC voltage output from the bidirectional converter are superimposed, and the superimposed DC voltage is supplied to the inverter for driving the compressor.

JP 2001-65927 A

  In order to prevent leakage current between the DC power supply and the AC power supply, the inventors of the present application completely switched between power supply from a DC power supply such as a storage battery and power supply from a commercial AC power supply, and Is developing air conditioners that supply only compressor power to the compressor. Such an air conditioner is not known at the time of filing of the present application.

  In this power switching type air conditioner, since the output of a DC power source such as a storage battery is limited, an AC power source is used when starting up the compressor, and then the power source is switched from the AC power source to the DC power source. Then, when the power is switched, a device with relatively large power consumption such as a compressor is stopped. However, once the compressor is stopped, when the compressor is restarted, it takes a few minutes to completely eliminate the pressure difference between the inlet and the outlet of the compressor. For this reason, there exists a possibility that room temperature may fluctuate | variate greatly during the temporary stop period of this compressor.

  The present invention has been made in consideration of the above-mentioned problems, and the object thereof is an air conditioner of a system in which power supply from a DC power supply and power supply from an AC power supply are switched and supplied to a compressor. It is an object of the present invention to provide an air conditioner that can suppress fluctuations in room temperature as much as possible when switching power from an AC power supply to a DC power supply. Other novel features and advantages of the present invention will become apparent from the accompanying drawings and detailed description.

  An air conditioner according to an aspect of the present invention includes a refrigerant circuit, a power supply circuit, and a control unit. The refrigerant circuit includes an outdoor heat exchanger, an indoor heat exchanger, an expansion valve, and a compressor. The power supply circuit is connected to an AC power supply and a DC power supply, and drives the compressor based on only one of the AC power supply and the DC power supply. The control unit starts the compressor based on the AC power supply, controls the power supply circuit so that the compressor is temporarily stopped when a predetermined switching condition is satisfied, and the compressor is restarted based on the DC power supply. To do. The above switching condition includes a condition that a predetermined first time has elapsed since the room temperature reached the temperature range corresponding to the set temperature.

  Preferably, the switching condition is that, when the outside air temperature is equal to or lower than the first specified temperature during the cooling operation, the first time has elapsed since the room temperature reached the temperature region. When the temperature is higher than 1 stipulated temperature, it means that a time obtained by adding a predetermined second time to the first time has elapsed since the room temperature reached the temperature region.

  Preferably, the switching condition is that, when the outside air temperature is equal to or higher than the second specified temperature during the heating operation, the first time has elapsed since the room temperature reached the temperature region. When the temperature is lower than the specified temperature of 2, the time obtained by adding a predetermined second time to the first time has elapsed since the room temperature reached the temperature region.

  Preferably, the switching condition is that when the absolute value of the temperature difference between the room temperature and the set temperature at the time of starting the compressor is equal to or greater than the specified temperature difference, the first time has elapsed since the room temperature reached the temperature range. When the absolute value of the temperature difference between the room temperature and the set temperature at the time of starting the compressor is smaller than the specified temperature difference, a third value determined in advance from the first time after the room temperature reaches the temperature region. That is, the time that you reduced the time has passed.

  An air conditioner according to another aspect of the present invention includes a refrigerant circuit, a power supply circuit, and a control unit. The refrigerant circuit includes an outdoor heat exchanger, an indoor heat exchanger, an expansion valve, and a compressor. The power supply circuit is connected to an AC power supply and a DC power supply, and drives the compressor based on only one of the AC power supply and the DC power supply. The control unit starts the compressor based on the AC power supply, controls the power supply circuit so that the compressor is temporarily stopped when a predetermined switching condition is satisfied, and the compressor is restarted based on the DC power supply. To do. The switching condition includes a condition that a predetermined first time has elapsed since the frequency of the compressor has become equal to or lower than the specified frequency due to the room temperature approaching the set temperature.

  Preferably, the switching condition is that, when the outside air temperature is equal to or lower than the first specified temperature during the cooling operation, the first time has elapsed since the frequency of the compressor is equal to or lower than the specified frequency. When the outside air temperature is higher than the first specified temperature, a time obtained by adding a predetermined second time to the first time after the frequency of the compressor becomes equal to or lower than the specified frequency has elapsed.

  Preferably, the switching condition is that when the outside air temperature is equal to or higher than the second specified temperature during the heating operation, the first time has elapsed since the frequency of the compressor is equal to or lower than the specified frequency. When the outside air temperature is lower than the second specified temperature, the time obtained by adding a predetermined second time to the first time after the frequency of the compressor becomes equal to or lower than the specified frequency has elapsed.

  Preferably, when the absolute value of the temperature difference between the room temperature and the set temperature at the start of the compressor is equal to or greater than the specified temperature difference, the switching condition is the first time after the compressor frequency becomes equal to or less than the specified frequency. When the absolute value of the temperature difference between the room temperature and the set temperature at the time of starting the compressor is smaller than the specified temperature difference, the first time after the compressor frequency becomes equal to or lower than the specified frequency. The time obtained by subtracting a predetermined third time from elapses.

  In the one aspect and the other aspect described above, preferably, the refrigerant circuit switches the refrigerant flow path compressed by the compressor to the outdoor heat exchanger side in order to switch the operation mode of the air conditioner between the cooling operation and the heating operation. And a four-way valve that switches between the indoor heat exchanger side. When the control unit detects frost formation in the outdoor heat exchanger during heating operation by driving the compressor based on a direct current power supply, the control unit temporarily stops the four-way valve for outdoor heat. After switching to the exchanger side, the power supply circuit is controlled to restart the compressor based on the AC power supply.After that, when the defrosting completion of the outdoor heat exchanger is detected, the compressor is temporarily stopped, After switching the four-way valve to the indoor heat exchanger side, control the power supply circuit to restart the compressor based on the AC power supply, and then stop the compressor once the switching condition is satisfied, and switch to the DC power supply Based on this, the power supply circuit is controlled to restart the compressor.

  According to the present invention, in an air conditioner that switches between power supply from a DC power supply and power supply from an AC power supply and supplies the compressor, a change in room temperature is caused when the power supply is switched from the AC power supply to the DC power supply. It can be suppressed as much as possible.

It is a figure for demonstrating the connection of the air conditioner by 1st Embodiment, DC power supply, and commercial AC power supply. It is a figure which shows typically the structure of the refrigerant circuit 10 of the air conditioner 50 of FIG. It is a figure which shows the electric system structure of the air conditioner of FIG. It is a flowchart which shows the switching procedure of the operation mode of the air conditioner of FIG. It is a flowchart which shows the procedure which determines whether AC / DC switching conditions are satisfy | filled. It is a flowchart which shows the procedure for determining whether AC / DC switching conditions are satisfy | filled at the time of air_conditionaing | cooling operation in the air conditioner of 2nd Embodiment. It is a flowchart which shows the procedure for determining whether AC / DC switching conditions are satisfy | filled at the time of heating operation in the air conditioner of 2nd Embodiment. It is a flowchart which shows the procedure for determining whether AC / DC switching conditions are satisfy | filled at the time of air_conditionaing | cooling operation in the air conditioner of 3rd Embodiment. It is a flowchart which shows the switching procedure of DC / AC operation mode at the time of a defrost operation in the air conditioner of 4th Embodiment. It is a flowchart of the modification of FIG. It is a flowchart of the modification of FIG. It is a flowchart of the modification of FIG. It is a flowchart of the modification of FIG.

  Hereinafter, each embodiment will be described in detail with reference to the drawings. In addition, the same reference number is attached | subjected to the part which is the same or it corresponds, and the description may not be repeated.

<First Embodiment>
[DC power supply and connection method between AC power supply and air conditioner]
Drawing 1 is a figure for explaining connection with an air harmony machine by a 1st embodiment, DC power supply, and commercial AC power supply. FIG. 1 shows an example in which a storage battery 41 is used as a DC power source.

  Referring to FIG. 1, the air conditioner 50 includes an indoor unit 60 and an outdoor unit 70. In the first embodiment, a commercial AC voltage with a rating of 200 V is input to the indoor unit 60, and a DC voltage with a rating of 100 V is input from the storage battery 41 to the outdoor unit 70.

  Specifically, as shown in FIG. 1, a terminal 42 (positive side terminal 42P, negative side terminal 42N) of the storage battery 41 and a terminal 72 (positive side terminal 72P, negative side terminal 72N) of the outdoor unit 70 are connected to DC. It is connected via a (direct current) 100V power line 54. The outlet plug 51 of the indoor unit 60 is connected to a single-phase three-wire 200V commercial AC power supply. That is, AC (alternating current) 200 V is applied between the terminals 51R and 51S of the outlet plug 51. A ground wire is connected to the terminal 51 </ b> O of the outlet plug 51.

  Furthermore, the indoor unit 60 and the outdoor unit 70 are provided with 3p terminals 61 and 71, respectively. The terminals 61R and 61S of the indoor unit 60 and the terminals 71R and 71S of the outdoor unit 70 are connected by a power line 52 of AC200V, and the terminal 61C of the indoor unit 60 and the terminal 71C of the outdoor unit 70 are communication lines 53. Connected by.

  In addition, unlike the case of this embodiment shown in FIG. 1, the structure by which both DC power supply and AC power supply are connected to the indoor unit 60 may be sufficient. In this case, either the direct current obtained by rectifying the alternating current from the alternating current power supply or the direct current from the direct current power supply is supplied to the outdoor unit 70.

[Configuration of refrigerant circuit of air conditioner]
FIG. 2 is a diagram schematically showing the configuration of the refrigerant circuit 10 of the air conditioner 50 of FIG. With reference to FIG. 2, the refrigerant circuit 10 includes a compressor 84 provided in the outdoor unit 70, an outdoor heat exchanger 35, an expansion valve 88, a four-way valve 90, and an indoor heat exchanger provided in the indoor unit 60. 36. Further, the outdoor unit 70 of the air conditioner 50 includes an outdoor fan 86, and the indoor unit 60 includes an indoor fan 65.

  The compressor 84 compresses the refrigerant. The outdoor heat exchanger 35 exchanges heat between outdoor air and refrigerant. The opening degree of the expansion valve 88 is controlled in order to adjust the flow rate of the refrigerant. The indoor heat exchanger 36 exchanges heat between indoor air and refrigerant. The outdoor fan 86 promotes heat exchange in the outdoor heat exchanger by blowing outdoor air to the outdoor heat exchanger 35. The indoor fan 65 blows the air heat-exchanged by the indoor heat exchanger 36 into the room. In the present embodiment, the outdoor fan 86 is configured by a propeller fan, and the indoor fan 65 is configured by a cross flow fan.

  The four-way valve 90 switches the circulation direction of the refrigerant in the cooling operation and the heating operation. During the cooling operation, as indicated by the solid line arrows in FIG. 2, the refrigerant is in the order of the compressor 84, the four-way valve 90, the outdoor heat exchanger 35, the expansion valve 88, the indoor heat exchanger 36, the four-way valve 90, and the compressor 84. Goes around. In this case, the outdoor heat exchanger 35 functions as a condenser for condensing and liquefying the compressed high-temperature refrigerant, and the indoor heat exchanger 36 evaporates the liquefied refrigerant so that the refrigerant is cooled to a low temperature. It functions as an evaporator for changing to gas.

  On the other hand, during the heating operation, as indicated by the broken-line arrows in FIG. 2, the compressor 84, the four-way valve 90, the indoor heat exchanger 36, the expansion valve 88, the outdoor heat exchanger 35, the four-way valve 90, and the compressor 84 The refrigerant circulates in order. In this case, the outdoor heat exchanger 35 functions as an evaporator, and the indoor heat exchanger 36 functions as a condenser.

  The air conditioner 50 further includes a temperature sensor 31 for measuring the temperature of the outdoor heat exchanger 35, a temperature sensor 30 for measuring a discharge temperature, which is a refrigerant temperature at the outlet of the compressor 84, and indoor heat. And a temperature sensor 33 for measuring the temperature of the exchanger 36. These temperature sensors 31, 30, 33 are, for example, thermistors. The temperature sensor 31 for the outdoor heat exchanger 35 and the temperature sensor 33 for the indoor heat exchanger 36 are both arranged between the inlet and the outlet of the heat exchanger. Therefore, in normal cases, the temperature detected when these heat exchangers function as a condenser is the refrigerant condensation temperature, and the temperature detected when they function as an evaporator is the refrigerant evaporation temperature. is there.

  Furthermore, a temperature sensor 32 for measuring the outside air temperature is attached to the outdoor unit 70, and a temperature sensor 34 for measuring the room temperature is attached to the indoor unit 60. These temperature sensors 32 and 34 can also be constituted by a thermistor, for example.

  In the present embodiment, the heating operation and the cooling operation are described as being switchable, but the air conditioner may be capable of only one of the heating operation and the cooling operation. In that case, the refrigerant circuit 10 is not provided with the four-way valve 90, and the functions of the outdoor heat exchanger 35 and the indoor heat exchanger 36 are fixed as a condenser or an evaporator. In addition, unlike the case of FIG. 2, the following technique can be applied to an integrated air conditioner that is not separated into the outdoor unit 70 and the indoor unit 60.

[Electric system configuration of air conditioner]
(Configuration of indoor unit)
FIG. 3 is a diagram showing an electrical system configuration of the air conditioner of FIG. Referring to FIG. 3, indoor unit 60 includes an indoor unit power supply circuit 62, an internal circuit 63, a relay 64 (open / close switch), and an indoor fan 65.

  The indoor unit power supply circuit 62 is connected to the outlet plug 51 and generates a DC voltage to be supplied to the internal circuit 63 based on the AC voltage (AC200V) received from the commercial AC power supply. The indoor unit power supply circuit 62 further includes a drive circuit (not shown) for driving a fan motor for the indoor fan 65. In addition, the power supply circuit 20 for the air conditioner 50 is comprised together with the power supply circuit 62 for indoor units, and the power supply circuit 21 for outdoor units mentioned later.

  The internal circuit 63 includes, for example, a communication circuit (not shown) for communication with the remote controller, a communication circuit 67 for communication with the outdoor unit 70, and the like. The communication circuit 67 is connected to the communication circuit 94 of the outdoor unit 70 via the communication line 53.

  The AC voltage (AC 200 V) input from the outlet plug 51 is input to the outdoor unit 70 via the terminals 61R and 61S, the power supply line 52, and the terminals 71R and 71S. The four-way valve 90 of the outdoor unit 70 is directly driven by this AC voltage. A relay 64 (open / close switch) is provided on a line connecting the outlet plug 51 and the terminals 61R and 61S.

(Configuration of outdoor unit)
The outdoor unit 70 includes an outdoor unit power supply circuit 21, a compressor 84 driven by the power supply circuit 21, an outdoor fan 86, an expansion valve 88, a microcomputer 89, and a communication circuit 94. Furthermore, the outdoor unit 70 includes a four-way valve 90 that is driven by an AC voltage supplied via the indoor unit 60.

  The outdoor unit power circuit 21 includes relays 73, 92, and 93 (open / close switches), a PTC thermistor (Positive Temperature Coefficient Thermistor) 74, and a current transformer (CT) as an AC ammeter A2. A full wave rectifier circuit 75, a switching circuit 76, a filter circuit 79, a diode 80, and a detection resistor as a DC voltmeter V1 and a DC ammeter A1.

  The AC voltage (AC 200V) input via the terminals 71R and 71S is input to the full-wave rectifier circuit 75 configured by a diode bridge via the relay 73 (open / close switch). The rectified voltage output from the full wave rectifier circuit 75 is input to the switching circuit 76. In order to reduce the magnetizing inrush current when the relay 73 is turned on, a PTC thermistor (Positive Temperature Coefficient Thermistor) 74 is connected in parallel with the relay 73. A PTC thermistor is an electronic component that has a substantially constant resistance value near room temperature, but the resistance value rapidly increases when a certain temperature is exceeded. The AC ammeter A2 is connected between the relay 73 and the rectifier circuit 75, and measures an AC current input to the indoor unit 60 (current consumption of the outdoor unit 70 during AC operation).

  On the other hand, the DC voltage (DC 100V) input via the terminals 72P and 72N is input to the filter circuit 79 via the relays 92 and 93 (open / close switch). The filter circuit 79 is a low-pass filter that blocks high-frequency components. The DC voltage output from the filter circuit 79 is input to the switching circuit 76 via the diode 80.

  The diode 80 is provided to protect the outdoor unit power supply circuit 21 when the polarity of a DC power supply such as a storage battery connected to the terminals 72P and 72N is reversed. That is, the diode 80 blocks a current in a direction that is input from the negative terminal 72N and output from the positive terminal 72P to the outside.

  The DC voltmeter V1 measures the voltage between the DC input terminals 72P and 72N. The DC ammeter V2 measures a DC current (current consumption of the outdoor unit 70 during DC operation) input from the DC power source to the outdoor unit 70.

  The switching circuit 76 includes relays 77 and 78 (switching switches). By switching the relays 77 and 78, one of the rectified voltage output from the full-wave rectifier circuit 75 and the DC voltage (DC 100V) is output.

  The outdoor unit power supply circuit 21 further includes a power factor improving step-up converter 81, a capacitor 82, a detection resistor as a voltmeter V3, inverters 83 and 85, and a step-down converter 87.

  A power factor correction (PFC) type boost converter 81 boosts the rectified voltage or DC voltage (DC 100 V) output from the switching circuit 76 to a set voltage (for example, DC 340 V). Further, when the input voltage is a rectified voltage, boost converter 81 operates as a power factor improvement circuit in a current continuous mode or a current critical mode, thereby matching the phases of the input voltage and the input current. A relatively large capacitor 82 and a voltmeter V3 are connected between the output nodes of boost converter 81. In order to reduce the output ripple of the boost converter 81, it is desirable to use an interleaved power factor correction circuit.

  The boosted voltage (DC 340 V) output from boost converter 81 is supplied to inverters 83 and 85 and step-down converter 87. The inverter 83 converts the boosted voltage into a three-phase AC voltage and supplies it to the synchronous motor of the compressor 84. The inverter 85 converts the boosted voltage into a three-phase AC voltage and supplies it to the synchronous motor for the outdoor fan 86. The step-down converter 87 steps down the step-up voltage (DC340V) to DC12V and supplies it to the stepping motor of the expansion valve 88, and steps down to DC5V and supplies it to the microcomputer 89 and the communication circuit 94.

  The microcomputer 89 has three-phase AC current detection values Iu1, Iv1, Iw1 detected by the shunt resistance provided in the inverter 83, and a three-phase AC current detection value detected by the shunt resistance provided in the inverter 85. Information on detection values of Iu2, Iv2, Iw2, and ammeters A1, A2 and voltmeters V1, V3 is input. Further, the microcomputer 89 receives information such as the room temperature, the outdoor temperature, the temperature of the indoor and outdoor heat exchangers (condensation temperature and evaporation temperature), and the rotational speed (also referred to as frequency) of the compressor. The microcomputer 89 controls the overall operation of the air conditioner 50 based on these pieces of information. Specifically, the microcomputer 89 controls the operation of the switching circuit 76, the boost converter 81, the inverter 83, the 85 step-down converter 87, the expansion valve 88, the four-way valve 90, and the like.

  In the case of FIG. 3, the four-way valve 90 operates with an AC voltage (AC 200 V), but may be replaced with one that operates with a DC voltage output from the step-down converter 87.

(About characteristics and effects of electrical system configuration)
The electrical system configuration is characterized in that one of a DC voltage and a rectified voltage is selectively input to the PFC boost converter 81 by providing a switching circuit 76 in the previous stage of the PFC boost converter 81. As a result, a DC / DC converter for a DC power supply and a boost converter for a power factor correction circuit, which have been provided separately in the past, can be combined into one.

  In FIG. 3, the rectifier circuit 75 is provided in the front stage of the switching circuit 76, but the rectifier circuit 75 may be provided in the rear stage of the switching circuit 76 and in front of the boost converter 81. When a DC voltage is input to the rectifier circuit 75, the DC voltage is output almost as it is, although there is some loss due to the diode.

  Furthermore, according to the above-described electric system configuration, the AC side and the DC side are insulated by the switching circuit 76, so that the problem of alternating current leakage current does not occur. Further, since the DC (direct current) operation based on the direct current power supply and the AC (alternating current) operation based on the alternating current power supply are performed independently, the user can determine whether the current operation state is the DC operation or the AC operation. By displaying on the screen, there is an advantage that the user can be encouraged to save energy.

[Air conditioner operation]
Hereinafter, the operation of the air conditioner having the electrical system configuration of FIG. 3 will be described. Hereinafter, a case where the switching circuit 76 is switched to the DC power supply side is referred to as a DC operation mode, and a case where the switching circuit 76 is switched to the AC power supply side is referred to as an AC operation mode. The switching procedure between the DC operation mode based on the DC power supply and the AC operation mode based on the AC power supply will be described in detail. The following steps are realized by executing a control program by the microcomputer 89 as a control unit.

  FIG. 4 is a flowchart showing a procedure for switching the operation mode of the air conditioner of FIG. Referring to FIGS. 3 and 4, when microcomputer 89 receives an operation start command from the user (YES in step S <b> 100), microcomputer 89 switches the switching circuit 76 to the AC power supply side (step S <b> 105), thereby causing AC operation mode Then, the operation of the air conditioner 50 is started (step S110). As described above, the reason why the AC operation mode is set at the start of the operation of the air conditioner is that the compressor 84 often rotates at a high speed because the difference between the room temperature and the set temperature is large when the air conditioner 50 is started. This is because the power consumption of the air conditioner 50 is increased.

  The microcomputer 89 switches the operation mode from the AC operation mode to the DC operation mode when the operation state of the air conditioner 50 is stabilized after a while. Specifically, the microcomputer 89 switches to the DC operation mode when a predetermined AC / DC (AC / DC) switching condition is satisfied (YES in step S115). The AC / DC switching condition will be described in detail with reference to FIG.

  If the above AC / DC switching condition is not satisfied (NO in step S115), the microcomputer 89 stops the operation of the air conditioner 50 by receiving an operation stop command from the user (YES in step S120) ( Unless it is step S125), the AC operation mode is continued.

  On the other hand, the procedure for switching the operation mode when the AC / DC switching condition is satisfied (YES in step S115) is as follows. First, the microcomputer 89 stops the AC operation of the outdoor unit 70 (specifically, the compressor 84 and the outdoor fan 86) (step S130), and then switches the switching circuit 76 from the AC power source side to the DC power source side. (Step S135). Thereafter, the microcomputer 89 starts DC operation of the outdoor unit 70 (specifically, the compressor 84 and the outdoor fan 86) (step S140). However, when the compressor 84 is restarted, a time of about 2 to 3 minutes must be allowed until the pressure difference between the inlet and the outlet of the compressor is completely eliminated.

  During the switching of the operation mode, the microcomputer 89 is operated by the charging voltage of the capacitor 82. In other words, the compressor 84, the outdoor fan 86, and the like having large power consumption must be stopped so that the microcomputer 89 can operate only with the charging voltage of the capacitor 82 during the switching of the operation mode. Unlike the electrical system configuration shown in FIG. 3, the microcomputer 89 can be driven only by an AC power source. However, also in this case, at least the compressor 84 with large power consumption must be stopped.

  After switching to the DC operation mode, the microcomputer 89 satisfies the DC / AC (DC / AC) switching condition (YES in step S145) or receives an operation stop command from the user (step S165). YES) Unless the operation of the air conditioner 50 is stopped, the DC operation mode is continued. The DC / AC switching condition is, for example, that the consumption current of the outdoor unit 70 during direct current operation measured by the ammeter A1 in FIG. 3 exceeds a specified value, or the direct current measured by the ammeter A1 and the voltmeter V1. For example, the power consumption of the outdoor unit 70 in the operation mode has exceeded a specified value, or the remaining amount of the storage battery has decreased to a specified amount or less.

  The operation mode switching procedure when the DC / AC switching condition is satisfied (YES in step S145) is as follows. First, the microcomputer 89 stops the DC operation of the outdoor unit 70 (specifically, the compressor 84 and the outdoor fan 86) (step S150), and then switches the switching circuit 76 from the DC power source side to the AC power source side. Switching is performed (step S155). Thereafter, the microcomputer 89 starts AC operation of the outdoor unit 70 (specifically, the compressor 84 and the outdoor fan 86) (step S160).

  As described above, energy saving is realized by effectively using a DC power source such as the storage battery 41 by switching from the AC operation mode to the DC operation mode based on the determination as to whether or not the AC / DC switching condition is satisfied. can do.

[AC / DC switching condition]
FIG. 5 is a flowchart showing a procedure for determining whether or not the AC / DC switching condition is satisfied. Hereinafter, switching from the AC operation mode to the DC operation mode will be described in more detail with reference to specific examples with reference to FIGS. In addition, the numerical value shown below is an example, Comprising: It is not limited to this numerical value.

  For example, it is assumed that the cooling operation is started at a set temperature of 26 ° C. when the outside air temperature and the room temperature are both 35 ° C. (step S110 in FIG. 4). At the start of operation, the operation mode is AC. Since there is a difference of 9 ° C. between the room temperature (35 ° C.) at the start of operation and the set temperature (26 ° C.), the microcomputer 89 rotates the compressor 84 at a relatively high speed to thereby output the compressor 84. Make it high.

  After the start of operation, the microcomputer 89 reads the room temperature by the temperature sensor 34 in FIG. 2 (step S210 in FIG. 5) and determines whether or not the room temperature has reached the set temperature (26 ° C.) (step S220). .

  When the room temperature reaches the set temperature (26 ° C.) in about 15 to 40 minutes (YES in step S220), the microcomputer 89 reduces the rotation speed of the compressor 84 so that the room temperature can be maintained. Adjust to. At this time, since the power consumption of the compressor 84 is decreasing, it is possible to immediately switch to the DC operation mode. However, at this time, the temperature of the indoor air is 26 ° C., but heat still accumulates on the ceiling, floor, and walls. For this reason, if the compressor is stopped for about 3 minutes when switching the operation mode, the room temperature rises by about 2 ° C. during that time. Meanwhile, the indoor fan 65 is rotating but the circulation of the refrigerant is stopped, so that the indoor environment becomes uncomfortable.

  Therefore, the microcomputer 89 continues to operate the compressor 84 as it is with the AC power supply for a while after the room temperature reaches the set temperature. When T time (for example, T = 20 minutes) has elapsed since the room temperature reached the set temperature (YES in step S260), the microcomputer 89 can switch the operation mode from the AC operation mode to the DC operation mode. It is determined that there is (step S290), that is, the AC / DC switching condition is satisfied (YES in step S115).

  Thereby, the microcomputer 89 stops the compressor 84 (step S130), switches the switching circuit from the AC side to the DC side (step S135), and after about 3 minutes (this time depends on the specifications of the compressor) 84 is restarted (step S140). By controlling the operation mode from AC operation to DC operation 20 minutes after the room temperature reaches the set temperature as described above, the temperature rise at room temperature when the operation mode is switched is suppressed to, for example, within about 0.5 ° C. Can do.

  In step S220, whether or not the room temperature has reached the set temperature is used as a criterion. Instead, whether the room temperature has reached a temperature range corresponding to the set temperature (for example, set temperature ± 0.5 ° C.). Whether or not it may be used as a criterion. In this case, in step S260, it is determined that the operation mode can be switched after a lapse of T time after the room temperature reaches the temperature range.

  Further, in the heating operation, as in the case of the cooling operation, a predetermined T time after the room temperature reaches the temperature range corresponding to the set temperature (this T time does not have to be the same as in the cooling operation). After elapses, the operation mode is switched from the AC operation mode to the DC operation mode. As a result, since the operation mode is switched after sufficient heat is stored in the ceiling, floor, and wall, the temperature drop at room temperature when the operation mode is switched can be suppressed to, for example, within about 2 ° C.

[effect]
As described above, according to the air conditioner of the first embodiment, the drive of the compressor based on the AC power supply is maintained for a while even when the room temperature reaches the temperature range corresponding to the set temperature, and a predetermined T time is reached. After that, the power supply source to the compressor is switched from the alternating current to the direct current power source. As a result, when the power source is switched from the AC power source to the DC power source, the change in the room temperature can be minimized.

<Second Embodiment>
[Features and effects]
In the second embodiment, a case where the outside air temperature during the cooling operation is higher or the outside air temperature during the heating operation is lower will be described.

  When the outside air temperature during cooling operation is higher, the duration of AC operation after the room temperature reaches the temperature range corresponding to the set temperature is changed from T time (about 20 minutes) to a longer time (T + α time) To do. As a result, the heat stored in the ceiling, floor, and walls of the room can be dissipated more sufficiently, and as a result, an increase in room temperature when switching the operation mode can be suppressed even when the outside air temperature is higher. .

  If the outside air temperature during heating operation is lower, the duration of AC operation after the room temperature reaches the temperature range corresponding to the set temperature is changed from T time (about 20 minutes) to a longer time (T + α time) To do. As a result, heat can be more sufficiently stored in the ceiling, floor, and walls of the room, and as a result, even when the outside air temperature is lower, a decrease in room temperature when switching the operation mode can be suppressed.

  Hereinafter, the AC / DC switching condition will be described in detail with reference to the drawings. In addition, since the apparatus structure of an air conditioner is the same as the case of FIGS. 1-3, schematic operation is the same as FIG. 4, and description is not repeated.

[AC / DC switching conditions for cooling operation]
FIG. 6 is a flowchart illustrating a procedure for determining whether the AC / DC switching condition is satisfied during the cooling operation in the air conditioner of the second embodiment.

  2 to 4 and 6, after the start of the cooling operation (step S110), the microcomputer 89 determines whether or not the room temperature read by the temperature sensor 34 has reached the set temperature (step S110). S220). When the room temperature reaches the set temperature (YES in step S220), the microcomputer 89 reads the outside air temperature with the temperature sensor 32 (step S230), and determines whether or not the outside air temperature is higher than a predetermined specified temperature. (Step S240).

  If the outside air temperature is equal to or lower than the specified temperature (NO in step S240), the microcomputer 89 starts from the AC operation mode after elapse of a predetermined time T after the room temperature reaches the set temperature (YES in step S260). It is determined that the operation mode can be switched to the DC operation mode (step S290), that is, the AC / DC switching condition is satisfied (YES in step S115).

  On the other hand, when the outside air temperature is higher than the specified temperature (YES in step S240), the microcomputer 89 performs AC operation after a predetermined time T + α has elapsed after the room temperature reaches the set temperature (YES in step S260). It is determined that the operation mode can be switched from the mode to the DC operation mode (step S290), that is, the AC / DC switching condition is satisfied (YES in step S115).

  In step S220, whether or not the room temperature has reached the set temperature is used as a criterion. Instead, whether the room temperature has reached a temperature range corresponding to the set temperature (for example, set temperature ± 0.5 ° C.). Whether or not it may be used as a criterion. In this case, in step S260 (S270), it is determined that the operation mode can be switched after T time (T + α time) has elapsed since the room temperature reached the temperature range.

[AC / DC switching conditions for heating operation]
FIG. 7 is a flowchart illustrating a procedure for determining whether the AC / DC switching condition is satisfied during the heating operation in the air conditioner of the second embodiment.

  2 to 4 and 7, after the heating operation is started (step S110), the microcomputer 89 determines whether or not the room temperature read by the temperature sensor 34 has reached the set temperature (step S110). S220). When the room temperature reaches the set temperature (YES in step S220), the microcomputer 89 reads the outside air temperature by the temperature sensor 32 (step S230), and determines whether or not the outside air temperature is lower than a predetermined specified temperature. (Step S240A). This specified temperature is a lower temperature (for example, 5 ° C.), unlike the cooling operation (for example, 35 ° C.).

  When the outside air temperature is equal to or higher than the specified temperature (NO in step S240A), the microcomputer 89 starts from the AC operation mode after elapse of a predetermined T time after the room temperature reaches the set temperature (YES in step S260). It is determined that the operation mode can be switched to the DC operation mode (step S290), that is, the AC / DC switching condition is satisfied (YES in step S115).

  On the other hand, when the outside air temperature is lower than the specified temperature (YES in step S240A), microcomputer 89 performs AC operation after elapse of a predetermined T + α time after the room temperature reaches the set temperature (YES in step S260). It is determined that the operation mode can be switched from the mode to the DC operation mode (step S290), that is, the AC / DC switching condition is satisfied (YES in step S115).

  In step S220, whether or not the room temperature has reached the set temperature is used as a criterion. Instead, whether the room temperature has reached a temperature range corresponding to the set temperature (for example, set temperature ± 0.5 ° C.). Whether or not it may be used as a criterion. In this case, in step S260 (S270), it is determined that the operation mode can be switched after T time (T + α time) has elapsed since the room temperature reached the temperature range.

<Third Embodiment>
[Features and effects]
In the third embodiment, in both the cooling operation and the heating operation, the difference (absolute value) between the room temperature and the set temperature at the start of operation of the compressor is a predetermined temperature difference (for example, 3 ° C.). )) Will be described. In this case, the waiting time until the operation mode is switched after the room temperature reaches the set temperature is made shorter than the T time of the first embodiment (T-β time). This is because, when the temperature difference between the room temperature and the set temperature is relatively small, the temperature change at the time of switching the operation mode is considered to be relatively small. Thereby, the energy saving performance of an air conditioner can be improved by shifting to direct current operation at an earlier stage.

  Hereinafter, the AC / DC switching condition will be described in detail with reference to the drawings. In addition, since the apparatus structure of an air conditioner is the same as the case of FIGS. 1-3, schematic operation is the same as FIG. 4, and description is not repeated.

[AC / DC switching condition]
FIG. 8 is a flowchart illustrating a procedure for determining whether the AC / DC switching condition is satisfied during the cooling operation in the air conditioner of the third embodiment.

  2 to 4 and 8, the microcomputer 89 reads the room temperature at the start of the operation of the compressor 84 by the temperature sensor 34, calculates the absolute value of the difference between the room temperature and the set temperature, and stores it. . Next, it is determined whether or not the room temperature read by the temperature sensor 34 after starting the operation of the compressor 84 has reached the set temperature (step S220). When the room temperature reaches the set temperature (YES in step S220), the microcomputer 89 determines whether or not the absolute value of the difference between the room temperature and the temperature sensor 32 at the start of operation of the compressor is smaller than a predetermined specified value. Is determined (step S250).

  If the absolute value of the difference between the room temperature at the start of operation of the compressor and the temperature sensor 32 is equal to or greater than a predetermined value (NO in step S250), the microcomputer 89 indicates that the room temperature has reached the set temperature. After the elapse of a predetermined time T (YES in step S260), the operation mode can be switched from the AC operation mode to the DC operation mode (step S290), that is, the AC / DC switching condition is satisfied (step S290). It is determined YES in step S115.

  On the other hand, if the absolute value of the difference between the room temperature and the temperature sensor 32 at the start of operation of the compressor is smaller than a predetermined value (YES in step S250), the microcomputer 89 sets the room temperature to the set temperature. After elapse of a predetermined T-β time after reaching (YES in step S280), the operation mode can be switched from the AC operation mode to the DC operation mode (step S290), that is, the AC / DC switching condition is It is determined that the condition is satisfied (YES in step S115).

  The third embodiment can be combined with the second embodiment. For example, when the outside air temperature is higher than a specified temperature during cooling operation and the difference between the room temperature and the set temperature at the start of operation of the compressor is smaller than the specified temperature difference, the AC / DC is reached after the room temperature reaches the set temperature. The waiting time until the operation mode is switched is set to T + α−β.

  In step S220, whether or not the room temperature has reached the set temperature is used as a criterion. Instead, whether the room temperature has reached a temperature range corresponding to the set temperature (for example, set temperature ± 0.5 ° C.). Whether or not it may be used as a criterion. Also in this case, in step S260 (S280), it is determined that the operation mode can be switched after a lapse of T time (T-β time) after the room temperature reaches the temperature range.

<Fourth Embodiment>
[Overview and effects]
In the fourth embodiment, a procedure for switching between a DC power source and an AC power source when resuming the heating operation after switching from the heating operation to the defrosting operation will be described. The defrosting operation is an operation for removing frost when frost accumulates in the outdoor heat exchanger due to the outdoor environment during the heating operation. In the method called reverse defrosting, the outdoor heat exchanger is warmed and defrosted by switching the heating operation to the cooling operation (however, the indoor fan and the outdoor fan are stopped). Therefore, the room cannot be heated during the defrosting operation.

  The defrosting operation is performed by supplying power from an AC power supply (AC operation mode). The reason is as follows. First, in order to make the defrosting time as short as possible, the rotational speed of the compressor is increased during the defrosting operation. This is because the power consumption of the compressor is large. In addition, when the DC power source is a storage battery, it must be switched to power supply from the AC power source when the remaining amount of the storage battery decreases. This is because if such a situation occurs during the defrosting operation, the defrosting operation must be forcibly terminated in a state where the defrosting is incomplete.

  Since the room temperature often decreases after the defrosting operation, it is necessary to increase the rotational speed of the compressor. For this reason, a compressor is started by the electric power supply from AC power supply. After that, even if the room temperature reaches the set temperature, the compressor is continuously operated in the AC operation mode for a while until the indoor ceiling, wall, and floor are sufficiently warmed. When T time (for example, about 20 minutes) elapses after the room temperature reaches the set temperature, the AC operation mode is switched to the DC operation mode.

  As described in the second embodiment, when the outside air temperature is lower than the specified temperature, the room temperature decreases when switching to the DC operation mode by further sufficiently heating the ceiling, floor, and wall. Need to prevent. For this reason, the operation mode is switched from the AC operation mode to the DC operation mode when T + α time longer than T time elapses after the room temperature reaches the set temperature.

[Switching DC / AC operation mode during defrosting operation]
FIG. 9 is a flowchart illustrating a procedure for switching the DC / AC operation mode during the defrosting operation in the air conditioner of the fourth embodiment. In addition, the apparatus structure of an air conditioner is the same as the case of FIGS. 1-3, and since the outline of the switching procedure of DC / AC operation modes other than a defrost operation is the same as FIG. 4, description is not repeated.

  With reference to FIGS. 2 to 4 and 9, first, it is assumed that the heating operation is being executed in the DC operation mode (step S <b> 300). If the microcomputer 89 determines that the outdoor heat exchanger 35 is frosted (YES in step S305), it stops the compressor 84, the outdoor fan 86, and the indoor fan 65 (step S310). In addition, when the temperature of the outdoor heat exchanger 35 is lower than the normal temperature according to outdoor temperature, it can determine with having formed frost.

  Thereafter, the microcomputer 89 switches the four-way valve 90 so that the refrigerant compressed by the compressor 84 is supplied to the outdoor heat exchanger 35 side, switches the switching circuit 76 to the AC power source side, and restarts the compressor 84. to start. As a result, the defrosting operation is started (step S315). Note that there is a predetermined waiting time (about 2 to 3 minutes) before the compressor 84 is stopped and restarted.

  Next, when the microcomputer 89 determines that the defrosting of the outdoor heat exchanger 35 is completed due to, for example, the temperature of the outdoor heat exchanger 35 becoming higher than 0 ° C. (YES in step S320), the compressor The AC operation 84 is stopped (step S325).

  Thereafter, the microcomputer 89 switches the four-way valve 90 so that the refrigerant compressed by the compressor 84 is supplied to the indoor heat exchanger 36 side, and operates the compressor 84, the outdoor fan 86, and the indoor fan 65. Start. Thereby, the heating operation is started in the AC operation mode (step S330).

  After the start of the heating operation, the microcomputer 89 reads the room temperature by the temperature sensor 34 in FIG. 2 (step S335 in FIG. 5), and determines whether or not the room temperature has reached the set temperature (step S340).

  The microcomputer 89 can switch the operation mode from the AC operation mode to the DC operation mode after the elapse of a predetermined T time after the room temperature reaches the set temperature (YES in Step S345), that is, Step S350. It is determined that the AC / DC switching condition is satisfied (YES in step S115).

  The above steps S335 to S350 can be replaced with FIG. 7 of the second embodiment, or can be replaced with FIG. 8 of the third embodiment.

<Fifth Embodiment>
[Overview]
In the first to fourth embodiments, the operation mode is switched from the AC operation mode to the DC operation mode when T time (T + α or T−β depending on the case) elapses after the room temperature reaches the set temperature. On the other hand, in the fifth embodiment, when T time (T + α or T−β depending on the case) elapses after the frequency of the compressor 84 is lowered to the specified frequency, the AC operation mode is changed to the DC operation mode. The operation mode is switched.

  When the frequency of the compressor 84 is controlled by feedback control, when the room temperature approaches the set temperature, the frequency of the compressor 84 decreases to such an extent that the room temperature can be maintained at the set temperature. Therefore, essentially the same control is performed when the AC / DC operation mode is switched based on the room temperature and when the AC / DC operation mode is switched based on the frequency of the compressor 84. Will be. In the following, the change of the AC / DC operation mode based on the frequency of the compressor 84 from the previous embodiments will be described. The same or corresponding steps are denoted by the same reference numerals, and description thereof will not be repeated.

[Modification of First Embodiment]
FIG. 10 is a flowchart of a modification of FIG. In FIG. 10, step S220B is provided instead of steps S210 and S220 of FIG. In step S220B, it is determined whether or not the frequency of the compressor 84 has decreased to a specified frequency. When the frequency of the compressor 84 has decreased to the specified frequency (YES in step S220B), the process proceeds to step S260B.

  In FIG. 10, step S260B is provided instead of step S260 of FIG. In step S260B, it is determined whether or not a predetermined T time has elapsed since the frequency of the compressor 84 has decreased to a specified frequency. If T time has elapsed since the frequency of the compressor 84 has decreased to the specified frequency (YES in step S260B), the microcomputer 89 determines that the operation mode can be switched from the AC operation mode to the DC operation mode ( Step S290).

[Modification of Second Embodiment]
FIG. 11 is a flowchart of a modification of FIG. FIG. 12 is a flowchart of the modified example of FIG. 11 and 12, in addition to the same changes as in FIG. 10, step S <b> 270 </ b> B is provided instead of step S <b> 270 in FIGS. 6 and 7.

  Step 270B is executed when the outside air temperature is higher than the specified temperature in the cooling operation of FIG. 11 (YES in step S240), and is executed in the heating operation of FIG. 12 when the outside air temperature is lower than the specified temperature (YES in step S240A). Is done. In Step 270B, it is determined whether or not T + α time longer than T time has elapsed since the frequency of the compressor 84 decreased to the specified frequency. If T + α time has elapsed since the frequency of the compressor 84 has decreased to the specified frequency (YES in step S270B), the microcomputer 89 determines that the operation mode can be switched from the AC operation mode to the DC operation mode. (Step S290).

[Modification of Third Embodiment]
FIG. 13 is a flowchart of the modification of FIG. In FIG. 13, in addition to the same changes as in FIG. 10, step S280B is provided instead of step S280 in FIG.

  Step S280B is executed when the difference between the room temperature at the start of operation of the compressor and the set temperature is smaller than the specified value (YES in step S250), and T time after the frequency of the compressor 84 has decreased to the specified frequency. It is determined whether a shorter T-β time has elapsed. If T-β time has elapsed after the frequency of the compressor 84 has decreased to the specified frequency (YES in step S280B), the microcomputer 89 can switch the operation mode from the AC operation mode to the DC operation mode. Is determined (step S290).

[effect]
As described above, in the fifth embodiment, when T time (T + α or T−β depending on the case) elapses after the frequency of the compressor 84 decreases to the specified frequency, the operation is switched from the AC operation mode to the DC operation mode. The mode is switched. In this case, the same effects as those of the first to fourth embodiments already described can be obtained.

<Appendix>
A part of the invention disclosed by the above embodiment will be listed below.

  [1] An air conditioner 50 including the refrigerant circuit 10, the power supply circuit 20, and the control unit 89 is provided. The refrigerant circuit 10 includes an outdoor heat exchanger 35, an indoor heat exchanger 36, an expansion valve 88, and a compressor 84. The power supply circuit 20 is connected to an AC power supply and a DC power supply, and drives the compressor 84 based on only one of the AC power supply and the DC power supply. The control unit 89 starts the compressor 84 based on the AC power supply, temporarily stops the compressor 84 when a predetermined switching condition is satisfied, and restarts the compressor 84 based on the DC power supply. The power supply circuit 20 is controlled. The switching condition includes a condition that a predetermined first time T has elapsed after the room temperature has reached a temperature range corresponding to the set temperature.

  According to the above configuration, even when the room temperature reaches the temperature range corresponding to the set temperature, the compressor is driven based on the AC power supply for a while, and the power is supplied to the compressor after a predetermined T time has elapsed. The original is switched from AC current to DC power supply. As a result, when the power source is switched from the AC power source to the DC power source, the change in the room temperature can be suppressed as much as possible.

  [2] In the above [1], the switching condition is that, when the outside air temperature is equal to or lower than the first specified temperature during the cooling operation, the first time T has elapsed since the room temperature reached the temperature region, When the outside air temperature is higher than the first specified temperature during the cooling operation, a time obtained by adding a predetermined second time α to the first time T after the room temperature has reached the temperature range has elapsed. is there.

  According to the above configuration, when the outside air temperature during the cooling operation is relatively high, a waiting time until the power supply source is switched after the room temperature reaches the temperature range is increased. As a result, the heat stored in the indoor walls, ceiling, and floor is sufficiently dissipated, so that the change in room temperature can be suppressed as much as possible when the power source is switched from the AC power source to the DC power source.

  [3] In the above [1], the switching condition is that, when the outside air temperature is equal to or higher than the second specified temperature during the heating operation, the first time T has elapsed since the room temperature reached the temperature region. When the outside air temperature is lower than the second specified temperature during the heating operation, the time obtained by adding the predetermined second time α to the first time T after the room temperature reaches the temperature range has elapsed. is there.

  According to the above configuration, when the outside air temperature during the heating operation is relatively low, a waiting time until the power supply source is switched after the room temperature reaches the temperature range is increased. As a result, sufficient heat is stored in the walls, ceiling, and floor of the room, so that fluctuations in room temperature can be suppressed as much as possible when the power source is switched from the AC power source to the DC power source.

  [4] In the above [1], the switching condition is that when the absolute value of the temperature difference between the room temperature and the set temperature at the start of the compressor 84 is equal to or greater than the specified temperature difference, the room temperature reaches the above temperature range. The first time T has elapsed, and when the absolute value of the temperature difference between the room temperature and the set temperature at the time of starting the compressor is smaller than the specified temperature difference, the first time T is reached after the room temperature reaches the temperature range. That is, a time obtained by subtracting a predetermined third time β from the time T in FIG.

  As described above, when the temperature difference between the room temperature and the set temperature is relatively small, it is considered that the temperature change when the operation mode is switched is also relatively small. Therefore, the energy-saving performance of the air conditioner can be enhanced by shifting to DC operation earlier.

  [5] An air conditioner 50 including the refrigerant circuit 10, the power supply circuit 20, and the control unit 89 is provided. The refrigerant circuit 10 includes an outdoor heat exchanger 35, an indoor heat exchanger 36, an expansion valve 88, and a compressor 84. Power supply circuit 20 is connected to an AC power supply and a DC power supply, and inverter-drives compressor 84 based only on one of the AC power supply and the DC power supply. The control unit 89 activates the compressor 84 based on the AC power supply, temporarily stops the compressor 84 when a predetermined switching condition is satisfied, and restarts the compressor based on the DC power supply. The circuit 20 is controlled. The above switching condition includes a condition that a predetermined first time T has elapsed since the frequency of the compressor 84 has become equal to or lower than the specified frequency due to the room temperature approaching the set temperature.

  The configuration [5] corresponds to the above [1], and has the same effect as the above [1].

  [6] In the above [5], the switching condition is that when the outside air temperature is equal to or lower than the first specified temperature during the cooling operation, the first time T elapses after the frequency of the compressor 84 becomes equal to or lower than the specified frequency. If the outside air temperature is higher than the first specified temperature during the cooling operation, the second time α set in advance at the first time T after the frequency of the compressor 84 becomes equal to or lower than the specified frequency. It is that the time of adding has passed.

  The configuration [6] corresponds to the above [2], and has the same effect as the above [2].

  [7] In the above [5], the switching condition is that when the outside air temperature is equal to or higher than the second specified temperature during the heating operation, the first time T elapses after the frequency of the compressor 84 becomes equal to or lower than the specified frequency. When the outside air temperature is lower than the second specified temperature during the heating operation, the second time α set in advance at the first time T after the frequency of the compressor 84 becomes equal to or lower than the specified frequency. It is that the time of adding has passed.

  The configuration [7] corresponds to the above [3], and has the same effect as the above [3].

  [8] In the above [5], the switching condition is that if the absolute value of the temperature difference between the room temperature and the set temperature when the compressor 84 is started is greater than or equal to the specified temperature difference, the frequency of the compressor is less than the specified frequency. If the absolute value of the temperature difference between the room temperature and the set temperature at the start of the compressor 84 is smaller than the specified temperature difference, the frequency of the compressor 84 is specified. This is that the time obtained by subtracting the predetermined third time β from the first time T has elapsed since the frequency became lower than the frequency.

  The configuration [8] corresponds to the above [4] and has the same effect as the above [4].

  [9] In the above [1], [3] to [5], [7], [8], the refrigerant circuit 10 is a compressor for switching the operation mode of the air conditioner between the cooling operation and the heating operation. The four-way valve 90 further switches the refrigerant flow path compressed between the outdoor heat exchanger 35 side and the indoor heat exchanger 36 side. When the controller 89 detects the frost formation of the outdoor heat exchanger 35 during the heating operation by driving the compressor 84 based on the DC power supply, the controller 89 temporarily stops the compressor 84 to When switching the valve 90 to the outdoor heat exchanger 35 side and controlling the power supply circuit 20 to restart the compressor 84 based on the AC power supply, and then detecting the completion of defrosting of the outdoor heat exchanger 35 Controls the power circuit so that the compressor 84 is temporarily stopped, the four-way valve 90 is switched to the indoor heat exchanger 36 side, and then the compressor 84 is restarted based on the AC power supply. Is satisfied, the compressor 84 is temporarily stopped, and the power supply circuit 20 is controlled so as to restart the compressor 84 based on the DC power supply.

  In the case of restarting the compressor after the defrosting operation, the power supply source to the compressor can be switched from the AC power source to the DC power source when the same switching condition as described above is satisfied.

  It should be thought that embodiment disclosed this time is an illustration and restrictive at no points. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  DESCRIPTION OF SYMBOLS 10 Refrigerant circuit, 20 Power supply circuit, 21 Outdoor unit power supply circuit, 30, 31, 32, 33, 34 Temperature sensor, 35 Outdoor heat exchanger, 36 Indoor heat exchanger, 41 Storage battery, 50 Air conditioner, 51 Outlet plug , 60 indoor unit, 62 indoor unit power supply circuit, 65 indoor fan, 70 outdoor unit, 75 full-wave rectifier circuit, 76 switching circuit, 81 boost converter, 82 capacitor, 83, 85 inverter, 84 compressor, 86 outdoor fan, 87 step-down converter, 88 expansion valve, 89 microcomputer (control unit), 90 four-way valve.

Claims (9)

A refrigerant circuit including an outdoor heat exchanger, an indoor heat exchanger, an expansion valve, and a compressor;
A power supply circuit connected to an AC power supply and a DC power supply, and driving the compressor based only on one of the AC power supply and the DC power supply;
The power supply circuit is configured to start the compressor based on the AC power supply, stop the compressor once when a predetermined switching condition is satisfied, and restart the compressor based on the DC power supply. And a control unit for controlling
The switching condition includes an air conditioner including a condition that a predetermined first time has elapsed after the room temperature reaches a temperature range corresponding to a set temperature.   The switching condition is that, when the outside air temperature is equal to or lower than the first specified temperature during the cooling operation, the first time has elapsed since the room temperature reached the temperature range. 2. The method according to claim 1, wherein when the temperature is higher than the first specified temperature, a time obtained by adding a predetermined second time to the first time after the room temperature reaches the temperature range has elapsed. Air conditioner.   The switching condition is that when the outside air temperature is equal to or higher than the second specified temperature during the heating operation, the first time has elapsed since the room temperature reached the temperature region, and the outside air temperature during the heating operation is 2. The method according to claim 1, wherein when the temperature is lower than a second specified temperature, a time obtained by adding a predetermined second time to the first time after the room temperature reaches the temperature range is elapsed. Air conditioner.   The switching condition is that when the absolute value of the temperature difference between the room temperature at the time of starting the compressor and the set temperature is a specified temperature difference or more, the first time elapses after the room temperature reaches the temperature region. If the absolute value of the temperature difference between the room temperature at the start of the compressor and the set temperature is smaller than the specified temperature difference, from the first time after the room temperature reaches the temperature region. The air conditioner according to claim 1, wherein a time obtained by subtracting a predetermined third time has elapsed. A refrigerant circuit including an outdoor heat exchanger, an indoor heat exchanger, an expansion valve, and a compressor;
A power circuit connected to an AC power source and a DC power source, and driving the compressor based on only one of the AC power source and the DC power source; and
The power supply circuit is configured to start the compressor based on the AC power supply, stop the compressor once when a predetermined switching condition is satisfied, and restart the compressor based on the DC power supply. And a control unit for controlling
The switching condition includes an air conditioner including a condition that a predetermined first time has elapsed since the frequency of the compressor has become equal to or lower than a specified frequency due to the room temperature approaching a set temperature.   The switching condition is that when the outside air temperature is equal to or lower than the first specified temperature during the cooling operation, the first time has elapsed since the frequency of the compressor is equal to or lower than the specified frequency. Sometimes when the outside air temperature is higher than the first specified temperature, a time obtained by adding a predetermined second time to the first time after the frequency of the compressor becomes equal to or lower than the specified frequency. The air conditioner according to claim 5, wherein   The switching condition is that, when the outside air temperature is equal to or higher than the second specified temperature during the heating operation, the first time has elapsed since the frequency of the compressor is equal to or lower than the specified frequency. Sometimes, when the outside air temperature is lower than the second specified temperature, a time obtained by adding a predetermined second time to the first time after the frequency of the compressor becomes equal to or lower than the specified frequency. The air conditioner according to claim 5, wherein   When the absolute value of the temperature difference between the room temperature when starting the compressor and the set temperature is equal to or greater than a specified temperature difference, the switching condition is that the frequency of the compressor is equal to or less than the specified frequency. 1 has elapsed, and when the absolute value of the temperature difference between the room temperature and the set temperature at the start of the compressor is smaller than the specified temperature difference, the frequency of the compressor is equal to or less than the specified frequency. The air conditioner according to claim 5, wherein a time obtained by subtracting a predetermined third time from the first time has elapsed since becoming. The refrigerant circuit switches a refrigerant flow path compressed by the compressor to the outdoor heat exchanger side and the indoor heat exchanger side in order to switch the operation mode of the air conditioner between a cooling operation and a heating operation. Including a four-way valve to be switched at
The controller is
When frosting of the outdoor heat exchanger is detected during heating operation by driving the compressor based on the DC power supply, the compressor is temporarily stopped, and the four-way valve is Control the power supply circuit to restart the compressor based on the AC power supply after switching to the outdoor heat exchanger side,
Thereafter, when the defrosting completion of the outdoor heat exchanger is detected, the compressor is temporarily stopped, the four-way valve is switched to the indoor heat exchanger side, and then the compressor is turned on based on the AC power supply. Controlling the power supply circuit to restart,
After that, when the switching condition is satisfied, the compressor is temporarily stopped, and the power supply circuit is controlled to restart the compressor based on the DC power supply. The air conditioner according to any one of 8.

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