WO2024154293A1

WO2024154293A1 - Air conditioner

Info

Publication number: WO2024154293A1
Application number: PCT/JP2023/001505
Authority: WO
Inventors: 和徳畠山; 裕一清水
Original assignee: 三菱電機株式会社
Priority date: 2023-01-19
Filing date: 2023-01-19
Publication date: 2024-07-25

Abstract

An air conditioner (100) comprises: an indoor machine (20) to which an AC power supply voltage is applied from an AC power supply (10); an outdoor machine (40) which is electrically connected to the indoor machine (20) by a communication line (30) and a power supply line (31); an AC switch (25) for applying the AC power supply voltage from the indoor machine (20) to the outdoor machine (40); and a battery (80) which is configured to be connectable to the outdoor machine (40), and for which charging/discharging and step-up/step-down can be controlled. The outdoor machine (40) comprises: a compressor (60) that operates by receiving both or either of a first DC power supply voltage obtained by rectifying the AC power supply voltage, and a second DC power supply voltage applied from the battery (80); an outdoor machine fan (70); and an outdoor machine actuator (90).

Description

Air conditioners

This disclosure relates to a separate-type air conditioner in which the indoor unit and the outdoor unit are separate.

The refrigeration cycle device described in Patent Document 1 below discloses technology for using the battery to compensate for power capacity shortages when a large current is required, such as during startup, in an outdoor unit that houses a heat exchanger, a blower, a compressor, and a rechargeable battery that serves as the power source for the compressor.

JP 2008-39231 A

Patent Document 1 aims to use a battery to supplement power when a large current is required, such as during startup, and does not require a large-capacity battery because the power supply only needs to be assisted for a short period of time. For this reason, it is not envisaged that it will be able to operate in response to the unstable power generated by renewable energy sources, which have been increasing in recent years.

Furthermore, conventional technologies such as that described in Patent Document 1 do not anticipate operation in response to a demand response request from the power generation side. Therefore, conventional technologies are unable to reduce power consumption even when the power supply from the power generation side is poor. For this reason, the greater the reliance on renewable energy, the greater the impact of unstable generated power, which disrupts the balance between generated power and demanded power, and in the worst case scenario, can lead to a power outage.

The present disclosure has been made in consideration of the above, and aims to provide an air conditioner that can address the problem of unstable power supply caused by renewable energy, which has been increasing in recent years.

In order to solve the above-mentioned problems and achieve the object, the air conditioner according to the present disclosure includes an indoor unit to which an AC power supply voltage is applied from an AC power supply, an outdoor unit electrically connected to the indoor unit by a communication line and at least one power supply line, an AC switch for applying the AC power supply voltage from the indoor unit to the outdoor unit, and a DC power supply capable of charge/discharge and step-up/step-down control configured to be connectable to the outdoor unit. The outdoor unit includes an outdoor unit load that operates by receiving both or either one of a first DC power supply voltage obtained by rectifying the AC power supply voltage and a second DC power supply voltage applied from the DC power supply.

The air conditioner disclosed herein has the effect of addressing the problem of unstable power supply caused by renewable energy sources, which have been increasing in recent years.

FIG. 1 is a diagram showing a basic configuration example of an air conditioner according to a first embodiment. FIG. 2 is a diagram showing an example of the internal configuration of an indoor unit and an outdoor unit in an air conditioner according to the first embodiment; FIG. 1 is a first diagram illustrating the operation of an air conditioner according to a first embodiment of the present invention; FIG. 2 is a second diagram illustrating the operation of the air conditioner according to the first embodiment. FIG. 3 is a third diagram illustrating the operation of the air conditioner according to the first embodiment. FIG. 1 is a block diagram showing an example of a hardware configuration for implementing the functions of an indoor unit control unit and an outdoor unit control unit included in an air conditioner according to a first embodiment. FIG. 13 is a diagram showing an example of the internal configuration of an indoor unit and an outdoor unit in an air conditioner according to a second embodiment. FIG. 13 is a diagram showing a basic configuration example of an air conditioner according to a third embodiment. FIG. 13 is a diagram showing an example of the internal configuration of an indoor unit and an outdoor unit in an air conditioner according to a third embodiment. FIG. 10 is a diagram showing an example of an internal configuration of an indoor unit and an outdoor unit in an air conditioner according to a third embodiment, which is different from that shown in FIG. FIG. 13 is a diagram showing an example of the internal configuration of an indoor unit and an outdoor unit in an air conditioner according to a fourth embodiment.

The air conditioner according to the embodiment of the present disclosure will be described in detail below with reference to the attached drawings.

Embodiment 1.
FIG. 1 is a diagram showing a basic configuration example of an air conditioner 100 according to embodiment 1. As shown in FIG. 1, the air conditioner 100 according to embodiment 1 is a separate type air conditioner in which an indoor unit 20 and an outdoor unit 40 are configured as separate units. The outdoor unit 40 is electrically connected to the indoor unit 20 by a communication line 30 and at least one or more power lines 31. An AC power supply voltage is applied to the indoor unit 20 from an AC power supply 10. The outdoor unit 40 includes an outdoor unit board 50, a compressor 60, an outdoor unit fan 70, a battery 80, and an outdoor unit actuator 90. The battery 80 is a DC power supply capable of charge/discharge and step-up/step-down control. The compressor 60, the outdoor unit fan 70, and the outdoor unit actuator 90 are examples of outdoor unit loads. Demand information is input to the indoor unit 20. The demand information here includes a demand response request instructed or requested from the power generation side.

FIG. 2 is a diagram showing an example of the internal configuration of the indoor unit 20 and the outdoor unit 40 in the air conditioner 100 according to embodiment 1. The main components of the indoor unit 20 are shown on the left side of FIG. 2, and the main components of the outdoor unit 40 are shown on the right side of FIG. 2.

The outdoor unit board 50 is equipped with a rectifier 51 that rectifies the AC power supply voltage,

inverters

52 and 53, and an outdoor unit control unit 54 that controls the operation of the outdoor unit 40. The compressor 60 is connected to the inverter 52, and a compressor motor (not shown) provided in the compressor 60 is driven by a drive voltage applied from the inverter 52. The outdoor unit fan 70 is connected to the inverter 53, and a fan motor (not shown) provided in the outdoor unit fan 70 is driven by a drive voltage applied from the inverter 53.

Battery 80 is connected to DC bus 56, which is arranged between the DC output side of rectifier 51 and the DC input side of

inverters

52, 53. Examples of battery 80 include lithium ion batteries, potassium ion batteries, NaS batteries, redox flow batteries, and lead acid batteries, but any battery that can store power can be used.

When the AC power supply voltage is 100V, the output of the rectifier 51 is approximately 140V, and when the AC power supply voltage is 200V, the output of the rectifier 51 is approximately 280V. For this reason, the number of battery cells in the battery 80 is selected according to these AC power supply voltages. Note that when the AC power supply voltage is 100V, the rectifier 51 can be configured as a voltage doubler rectifier, so that the output can be approximately 280V, which is the same as when the AC power supply voltage is 200V.

Note that while FIG. 2 illustrates the battery 80 as an external component of the outdoor unit 40, if the battery 80 has a small capacity, the battery 80 may be built into the outdoor unit 40. In other words, the battery 80 only needs to be configured to be connectable to the DC bus 56 that electrically connects the rectifier 51 and the

inverters

52 and 53, and may be located either inside or outside the outdoor unit 40.

The outdoor unit actuator 90 is an actuator that operates by receiving both or either of the first DC power supply voltage applied via the rectifier 51 and the second DC power supply voltage applied from the battery 80. The first DC power supply voltage is a DC power supply voltage obtained by rectifying the AC power supply voltage. Examples of the outdoor unit actuator 90 include a four-way valve, an electronic expansion valve, and a heater. The

inverters

52, 53 and the outdoor unit control unit 54 also operate by receiving both or either of the first DC power supply voltage and the second DC power supply voltage.

The indoor unit 20 comprises an indoor unit board 21, an indoor unit actuator 24, and an AC switch 25. The indoor unit board 21 is equipped with a rectifier 22 and an indoor unit control unit 23. The AC switch 25 is a switch for applying an AC power supply voltage from the indoor unit 20 to the outdoor unit 40. The indoor unit actuator 24 is an actuator that operates with a third DC power supply voltage applied via the rectifier 22. The third DC power supply voltage is also a DC power supply voltage obtained by rectifying the AC power supply voltage. The indoor unit actuator 24 is an example of an indoor unit load, and examples of this include airflow direction changing blades, automatic cleaning filters, and various sensors. The indoor unit control unit 23 also operates by receiving the third DC power supply voltage.

The battery 80 also includes a DC/DC converter 82 that performs bidirectional DC (Direct Current) conversion between the battery 80 and the DC bus 56. The outdoor unit control unit 54 controls the DC/DC converter 82 to control the output voltage of the DC/DC converter 82 that is applied to the DC bus 56. The second DC power supply voltage described above is the output voltage of the battery 80 that has been stepped up or down by the DC/DC converter 82.

Next, the main points of the operation of the air conditioner 100 according to the first embodiment will be explained with reference to Figs. 3 to 5. Figs. 3 to 5 are the first to third figures used to explain the operation of the air conditioner 100 according to the first embodiment.

As shown in Figs. 3 and 4, the AC power supply voltage output by the AC power supply 10 is constantly applied to the indoor unit 20. On the other hand, in the outdoor unit 40, the AC power supply voltage is applied to the outdoor unit 40 by closing the AC switch 25.

The indoor unit control unit 23 controls the operation of the indoor unit actuator 24 and the AC switch 25. When the indoor unit control unit 23 receives an operation start command from a remote control (not shown), it closes the AC switch 25. By controlling in this way, it is expected that the standby power consumption can be reduced.

The outdoor unit control unit 54 controls the operation of the

inverters

52, 53, the DC/DC converter 82, and the outdoor unit actuator 90. The

inverters

52, 53 drive a compressor motor (not shown) provided in the compressor 60 and a fan motor (not shown) provided in the outdoor unit fan 70 based on control signals output from the outdoor unit control unit 54. Note that the control signals are not shown in Figures 3 and 4.

When there is no problem with receiving the AC power supply voltage, the outdoor unit 40 generates a first DC power supply voltage via the rectifier 51, and further charges the battery 80 via the DC/DC converter 82. When charging the battery 80, the AC switch 25 in the indoor unit 20 must be closed. When the AC switch 25 is open, the outdoor unit control unit 54 is not operating, making it difficult to grasp the charge level of the battery 80. Therefore, when the outdoor unit 40 finishes operating, information on the remaining charge of the battery 80 is transmitted to the indoor unit control unit 23. The indoor unit control unit 23 monitors the decrease in the battery 80, taking into account the natural discharge time, etc. When the charge level of the battery 80 decreases, the indoor unit 20 appropriately closes the AC switch 25 to charge the battery 80.

Furthermore, in the air conditioner 100 according to embodiment 1, as shown in FIG. 4, the battery 80 is charged by utilizing the rotation of the outdoor unit fan 70. In recent years, fan motors using permanent magnets have been widely used to drive the outdoor unit fan 70. When the outdoor unit fan 70 is rotated by an external force such as a strong wind, a generated voltage is generated. This generated voltage is rectified by the inverter 53 to become a DC voltage, which can be used to charge the battery 80. Furthermore, when the compressor 60 stops operating, the battery 80 can be charged by regenerating energy from the compressor motor.

The air conditioner 100 according to the first embodiment is configured to operate by receiving a demand signal. The demand signal includes a demand response request instructed or requested by the power generation side. When the indoor unit control unit 23 receives the demand signal, it controls the air conditioner 100 to reduce the power supplied from the AC power source 10. In general, upon receiving the demand signal, the indoor unit control unit 23 instructs the outdoor unit control unit 54 via the communication line 30 to make a demand response request, such as reducing the rotation speed to reduce the power consumption of the compressor 60, which consumes a lot of power. At this time, the operating capacity of the cooling or heating function is reduced, resulting in problems such as a longer time to reach the target set temperature or failure to reach the target set temperature.

In the air conditioner 100 according to the first embodiment, as shown in FIG. 3, power for driving the compressor 60 is supplied from a battery 80 connected to the outdoor unit 40. To enable this operation, the indoor unit control unit 23 charges the battery 80 via the outdoor unit control unit 54 when a demand signal is not being received.

When the air conditioner 100 according to the first embodiment limits the energy supply from the AC power source 10 by a demand signal, the outdoor unit 40 is operated using the power of the AC power source 10 and the battery 80 in combination, or only the power of the battery 80. When the outdoor unit 40 is operated using the power of the battery 80 only, the step-up ratio of the DC/DC converter 82 may be controlled so that the second DC power source voltage output from the battery 80 is higher than the first DC power source voltage output from the rectifier 51. To use the power of the AC power source 10 and the battery 80 in combination, the step-up ratio of the DC/DC converter 82 may be controlled so that the first DC power source voltage output from the rectifier 51 and the second DC power source voltage output from the battery 80 are equivalent. By operating in this manner, it is possible to contribute to the leveling out of the energy used in the power system.

Figure 5 shows an example of an operation that can contribute to leveling out the energy usage of a power system. Photovoltaic power generation, a typical renewable energy source, generates more power during the day when solar energy is easily obtained. In contrast, power generation decreases during times when it is difficult to obtain energy from the sun, such as in the morning or at night. In terms of power usage, while the morning is a time when it is difficult to obtain energy from solar power generation, it is also a time when people are busy with their activities after waking up and commuting to work or school. For this reason, air conditioners and other devices may operate simultaneously during this time, making it easy for power peaks to occur. When a power peak occurs, as shown in the upper part of Figure 5, a situation occurs in which power usage is higher than power generation, and in the worst case scenario, this could lead to a power outage.

The air conditioner 100 according to the first embodiment therefore charges the battery 80 during the daytime hours when there is a large amount of surplus power. As described above, the battery 80 is charged using regenerative power from the outdoor unit fan 70 and the compressor 60. When the air conditioner 100 receives a demand signal, it operates the outdoor unit 40 using the energy stored in the battery 80. This makes it possible to shift the morning power peak and distribute it to other times of the day. Furthermore, by using the stored energy in the battery 80, there is a surplus in the power generated by the power grid, making it possible to avoid power outages and the like that are caused by power peaks.

The above-mentioned power peak shifting and distributed control has limited effectiveness when performed on only one household, so it is desirable to perform it on multiple households. For example, multiple households can be divided into groups, and operation on battery 80 can be performed at different times for each group. Implemented in this way, it is possible to suppress peak power without concentrating the burden on one household. The number of groups and operation time on battery 80 can be set taking into account the amount of surplus power generation in the power grid.

The storage capacity of the battery 80 can be determined based on the target value of the peak power to be reduced, the time for power peak shift and distributed control, and the like. Here, an example will be described in which the renewable energy is solar power generation, the battery 80 is charged during the day when the power generated by solar power generation is high, and peak shift operation is performed at night when the supply is likely to be insufficient. Also, assume that the power consumption of the air conditioner 100 when the temperature is stable is 500 W, the nighttime time is 12 h (hours), and six households are using the air conditioner 100. In this case, in order to reduce the peak power of each household to 5/6, each household is operated so that they use the battery 80 for two different hours out of the 12 hours. In this operation, the number of households using the air conditioner 100 at the same time is reduced from 6 to 5, so the total power of the six households is reduced to 5/6. This allows the peak power to be reduced to 5/6.

Furthermore, the amount of power that one household's battery 80 requires for two hours of operation can be calculated as 500W x 2h = 1 kWh. This amount of power is the minimum storage capacity of the battery 80. In other words, the storage capacity of the battery 80 can be determined by the target value of the peak power to be reduced, the power peak shift, and the time for which distributed control is performed.

As described above, by using the air conditioner 100 according to the first embodiment, it is possible to address the problem of unstable power supply caused by renewable energy sources, which has been increasing in recent years.

Next, the hardware configuration of the indoor unit control unit 23 and outdoor unit control unit 54 provided in the air conditioner 100 will be described. FIG. 6 is a diagram showing an example of a hardware configuration that realizes each function of the indoor unit control unit 23 and outdoor unit control unit 54 provided in the air conditioner 100 according to embodiment 1. Each function of the indoor unit control unit 23 and outdoor unit control unit 54 is realized by the processor 200 and memory 202.

The processor 200 is a CPU (also called a Central Processing Unit, processing unit, arithmetic unit, microprocessor, microcomputer, processor, or DSP (Digital Signal Processor)) or a system LSI (Large Scale Integration). Examples of the memory 202 include non-volatile or volatile semiconductor memories such as RAM (Random Access Memory), ROM (Read Only Memory), flash memory, EPROM (Erasable Programmable Read Only Memory), and EEPROM (registered trademark) (Electrically Erasable Programmable Read Only Memory). Furthermore, the memory 202 is not limited to these, and may be a magnetic disk, optical disk, compact disk, mini disk, or DVD (Digital Versatile Disc).

As described above, the air conditioner according to the first embodiment includes an indoor unit to which an AC power supply voltage is applied from an AC power supply, an outdoor unit electrically connected to the indoor unit by a communication line and at least one power supply line, an AC switch for applying the AC power supply voltage from the indoor unit to the outdoor unit, and a DC power supply capable of charge/discharge and step-up/down control configured to be connectable to the outdoor unit. The outdoor unit includes an outdoor unit load that receives both or either of a first DC power supply voltage obtained by rectifying the AC power supply voltage and a second DC power supply voltage applied from the DC power supply. With the air conditioner configured in this way, the power supply to the outdoor unit load can be freely switched between the AC power supply and the DC power supply depending on the supply state of the AC power. Furthermore, with the air conditioner configured in this way, when the air conditioner is in an AC non-receiving operation in which the air conditioner operates without receiving the AC power supply voltage, the power supply to the outdoor unit load can be switched from the AC power supply to the DC power supply. This makes it possible to address the problem of power instability caused by renewable energy, which has been increasing in recent years.

Note that non-AC power receiving operation, in which the air conditioner operates without receiving AC power voltage, includes times when there is a power outage in the AC power supply and when a demand response request is issued to the air conditioner from outside. When a demand response request is issued, the air conditioner can adjust the amount of power supplied from the DC power supply based on the demand response request. Control in this way makes it possible to appropriately adjust the amount of power consumed by the air conditioner, which reduces the burden on the power grid and contributes to maintaining a stable power supply.

Furthermore, in the air conditioner according to embodiment 1, the DC power supply may be charged when the outdoor unit fan is rotated by an external force. In this way, the power generated by the outdoor unit fan can be used effectively. If many air conditioners perform this operation, it can greatly contribute to maintaining a stable power supply.

Furthermore, in the air conditioner according to embodiment 1, the outdoor unit control unit may be configured so that the second DC power supply voltage output from the DC power supply is constantly applied to it. If configured in this way, the outdoor unit control unit that controls the operation of the outdoor unit is constantly maintained in a controllable state. Therefore, when the DC power supply is a battery, there is no need for control to transmit information about the remaining charge of the battery to the indoor unit control unit when the outdoor unit has finished operating. This makes it possible to easily grasp the charge level of the battery without complicating the control.

In the air conditioner according to embodiment 1, the outdoor unit control unit may be configured to be started when the voltage of the DC bus to which the DC power source is connected reaches a specified voltage. In this configuration, if the DC power source is a battery, battery power is not consumed when the air conditioner is not operating, and the battery power can be used effectively. Even with this configuration, if information about the remaining battery charge is transmitted to the indoor unit control unit when the outdoor unit ends operation, the information about the remaining battery charge can be promptly received from the indoor unit control unit after the outdoor unit control unit is started, making it possible to reliably grasp the amount of charge in the battery.

Embodiment 2.
In the first embodiment, a configuration in which an AC power supply voltage is applied from the indoor unit 20 to the outdoor unit 40 has been described, but in the second embodiment, a configuration in which an AC power supply voltage is applied from the outdoor unit 40 to the indoor unit 20 will be described. Fig. 7 is a diagram showing an example of the internal configuration of the indoor unit 20 and the outdoor unit 40 in an air conditioner 100 according to the second embodiment.

In the configuration of the second embodiment, an AC switch 91 is provided on the outdoor unit 40 side, and an AC power source 10 is connected between the AC switch 91 and the rectifier 51. An AC power source voltage is applied to the indoor unit 20 by closing the AC switch 91. The other configuration is the same as the configuration of the first embodiment shown in FIG. 2, and the same components are given the same reference numerals and duplicated explanations are omitted.

In the case of the second embodiment, the AC power supply voltage is constantly applied to the outdoor unit 40, so the demand signal is received by the outdoor unit control unit 54. Generally, a communication environment such as a wireless router is constructed indoors, and communication via the Internet is assumed to be performed indoors. For this reason, as in the first embodiment, the demand signal may be received by the indoor unit control unit 23. However, in the case of the configuration of FIG. 7, the AC power supply voltage is not applied to the indoor unit 20 unless the AC switch 91 is closed. In addition, in the air conditioner 100, since it is common to send an operation start command to the indoor unit 20 using an infrared remote control or the like, the operation start command cannot be received unless power is supplied to the indoor unit 20. For this reason, the air conditioner 100 according to the second embodiment may be configured so that the AC power supply voltage is constantly applied to the indoor unit 20 and the outdoor unit 40 without providing the AC switch 91.

The air conditioner 100 according to the second embodiment is configured as described above, so when a demand signal is received, it can use power from the battery 80 to drive the compressor 60, the outdoor unit fan 70, and the outdoor unit actuator 90. This makes it possible to address the problem of power instability caused by the increasing use of renewable energy in recent years.

As described above, the air conditioner according to the second embodiment includes an outdoor unit to which an AC power supply voltage is applied from an AC power supply, an indoor unit electrically connected to the outdoor unit by a communication line and at least one power supply line, an AC switch for applying the AC power supply voltage from the outdoor unit to the indoor unit, and a DC power supply capable of charge/discharge and step-up/down control configured to be connectable to the outdoor unit. The outdoor unit includes an outdoor unit load that receives both or either of a first DC power supply voltage obtained by rectifying the AC power supply voltage and a second DC power supply voltage applied from the DC power supply. With the air conditioner configured in this way, the power supply to the outdoor unit load can be freely switched between the AC power supply and the DC power supply depending on the supply state of the AC power. Furthermore, with the air conditioner configured in this way, when the air conditioner is set to an AC non-receiving operation in which the air conditioner operates without receiving the AC power supply voltage, the power supply to the outdoor unit load can be switched from the AC power supply to the DC power supply. This allows for the same effects as those of the first embodiment to be obtained.

Embodiment 3.
Fig. 8 is a diagram showing an example of a basic configuration of an air conditioner 100 according to embodiment 3. Comparing the configuration of Fig. 8 with the configuration of Fig. 1, a DC power supply line 32 is added between the indoor unit 20 and the outdoor unit 40. The other configurations are the same or equivalent to those of embodiment 1 shown in Fig. 1, and the same or equivalent components are designated by the same reference numerals and redundant explanations will be omitted.

FIG. 9 is a diagram showing an example of the internal configuration of the indoor unit 20 and outdoor unit 40 in an air conditioner 100 according to embodiment 3. Also, FIG. 10 is a diagram showing an example of the internal configuration of the indoor unit 20 and outdoor unit 40 in an air conditioner 100 according to embodiment 3, which is different from that shown in FIG. 9. FIG. 9 shows a form in which an AC power supply voltage is applied from the indoor unit 20 to the outdoor unit 40. Also, FIG. 10 shows a form in which an AC power supply voltage is applied from the outdoor unit 40 to the indoor unit 20.

Comparing the configuration of FIG. 9 with the configuration of FIG. 2, one end of the DC power supply line 32 is connected to the DC bus 56, and the other end of the DC power supply line 32 is connected to the DC output side of the rectifier 22. The DC power supply line 32 is also provided with a DC switch 92 for applying the second DC power supply voltage to the indoor unit 20. The other configurations are the same or equivalent to those of the first embodiment shown in FIG. 2, and the same or equivalent components are designated by the same reference numerals, and duplicated explanations will be omitted.

Furthermore, comparing the configuration of FIG. 10 with the configuration of FIG. 7, one end of the DC power supply line 32 is connected to the DC bus 56, and the other end of the DC power supply line 32 is connected to the DC output side of the rectifier 22. The DC power supply line 32 is also provided with a DC switch 92 for applying the second DC power supply voltage to the indoor unit 20. The other configurations are the same or equivalent to those of the second embodiment shown in FIG. 7, and the same or equivalent components are designated by the same reference numerals, and duplicated explanations will be omitted.

Next, the main points of the operation of the air conditioner 100 according to the third embodiment will be described with reference to Figures 9 and 10. First, in the configurations of Figures 2 and 7, when the power supply from the AC power source 10 is cut off, there is no path for supplying power from the battery 80 to the indoor unit 20. Therefore, although the outdoor unit 40 can be operated, there is no means for operating the indoor unit 20, and therefore the air conditioner 100 cannot be operated.

It is conceivable to configure the rectifier unit 51 as a regenerative converter and supply power from the battery 80, but when the AC switch 25 and the AC switch 91 are open, it is difficult to supply power to the indoor unit 20. Furthermore, if the AC switch 25 and the AC switch 91 are closed, power is regenerated to the power grid during a power outage, and workers performing power recovery work may be electrocuted. For this reason, configuring the rectifier unit 51 as a regenerative converter poses a high hurdle to system construction. Therefore, in the third embodiment, the DC section of the outdoor unit 40 and the DC section of the indoor unit 20 are configured to be connected by the DC power line 32 via the DC switch 92.

According to the air conditioner 100 of embodiment 3, as shown in FIG. 9, even if the indoor unit 20 is configured to receive power, the outdoor unit 40 and the indoor unit 20 can be operated using the power of the battery 80 during a power outage of the AC power source 10.

Furthermore, according to the air conditioner 100 of embodiment 3, even if the outdoor unit 40 is configured to receive power as shown in FIG. 10, during a power outage of the AC power source 10, the outdoor unit 40 and the indoor unit 20 can be operated using the power of the battery 80.

Furthermore, according to the air conditioner 100 of embodiment 3, as shown in Figs. 9 and 10, the demand response request is received by either the indoor unit control unit 23 or the outdoor unit control unit 54, and the compressor 60 and the outdoor unit fan 70 can be driven using the power of the battery 80 even during a power outage of the AC power source 10.

As described above, the air conditioner according to embodiment 3, in the configurations of embodiments 1 and 2, further includes a DC switch for applying a second DC power supply voltage to the indoor unit. With this configuration, when the air conditioner is to operate in an AC non-receiving mode in which the air conditioner operates without receiving AC power supply voltage, the DC switch is closed to apply the second DC power supply voltage to the indoor unit. This makes it possible to obtain an air conditioner that can drive the compressor and outdoor unit using battery power, regardless of whether the receiver for the demand-response request is in the indoor unit control unit or the outdoor unit control unit, and even during a power outage of the AC power supply.

Embodiment 4.
In the air conditioner 100 according to the third embodiment, in addition to the communication line 30, it was necessary to wire a power line 31 for applying an AC power supply voltage to the indoor unit 20 or the outdoor unit 40 and a DC power supply line 32 for applying a second DC power supply voltage to the indoor unit 20 between the indoor unit 20 and the outdoor unit 40. This resulted in problems such as an increase in wiring between the indoor unit 20 and the outdoor unit 40, a problem that electrical wiring work is time-consuming at the stage of installing the air conditioner 100, and a need to make a large hole in the wall to pass refrigerant piping and connection lines between the indoor unit 20 and the outdoor unit 40. In order to solve these problems, the fourth embodiment proposes a configuration shown in FIG. 11. FIG. 11 is a diagram showing an example of the internal configuration of the indoor unit 20 and the outdoor unit 40 in the air conditioner 100 according to the fourth embodiment.

Comparing the configuration of FIG. 11 with the configuration of FIG. 10, the AC switch 91 arranged between the indoor unit 20 and the outdoor unit 40 has been deleted. Also, the power line 31 is arranged only in the outdoor unit 40, and the AC power supply voltage is applied only to the outdoor unit 40. As a result, the rectifier unit 22 that generated the third DC power supply voltage has been deleted from the indoor unit 20. The other configurations are the same or equivalent to those of the third embodiment shown in FIG. 10, and the same or equivalent components are designated by the same reference numerals, and duplicate explanations will be omitted.

In the air conditioner 100 according to the fourth embodiment, the rectifier 22 is not necessary, so it is possible to reduce the manufacturing costs of the indoor unit 20. Since the power line 31 between the indoor unit 20 and the outdoor unit 40 is not necessary, it is possible to reduce the labor required for electrical wiring work.

Furthermore, the power line 31, which is an AC power line arranged between the indoor unit 20 and the outdoor unit 40, can be several meters to several tens of meters long. As the wiring length of the power line 31 becomes longer, the wiring inductance increases, so losses increase and the effects of voltage drop become greater. On the other hand, the DC power line 32 is not affected by the wiring inductance, so it is possible to enjoy the advantage that the wiring length of the DC power line 32 can be made longer than that of the power line 31.

As described above, the air conditioner according to the fourth embodiment includes an outdoor unit to which an AC power supply voltage is applied from an AC power supply, an indoor unit electrically connected to the outdoor unit by at least a communication line, and a DC power supply capable of charge/discharge and step-up/down control configured to be connectable to the outdoor unit. The outdoor unit includes an outdoor unit load that operates by receiving both or either of a first DC power supply voltage obtained by rectifying the AC power supply voltage and a second DC power supply voltage applied from the DC power supply, a DC power supply line electrically connecting the indoor unit and a DC busbar of the outdoor unit to which the DC power supply is connected, and a DC switch for applying the first DC power supply voltage and the second DC power supply voltage to the indoor unit. With the air conditioner configured in this manner, the power supply to the outdoor unit load can be freely switched between the AC power supply and the DC power supply depending on the supply state of the AC power. Furthermore, with an air conditioner configured in this manner, when the air conditioner is in AC non-receiving mode, in which the air conditioner operates without receiving AC power voltage, the power supply to the outdoor unit load can be switched from the AC power source to the DC power source.

Furthermore, with the air conditioner according to embodiment 4, a rectifier is not required, so the manufacturing costs of the indoor unit can be reduced, and since an AC power line between the indoor unit and the outdoor unit is not required, the labor required for electrical wiring work can be reduced. Furthermore, with the air conditioner according to embodiment 4, a DC power line can be arranged instead of an AC power line, so it is possible to enjoy the advantage of being able to increase the length of the power line.

Furthermore, in the air conditioner according to embodiment 4, the DC power supply may be charged when the outdoor unit fan is rotated by an external force. In this way, the power generated by the outdoor unit fan can be used effectively. If many air conditioners perform this operation, it can greatly contribute to maintaining a stable power supply.

Furthermore, in the air conditioner according to embodiment 4, the outdoor unit control unit may be configured so that the second DC power supply voltage output from the DC power supply is constantly applied to it. If configured in this way, the outdoor unit control unit that controls the operation of the outdoor unit is constantly maintained in a controllable state. Therefore, when the DC power supply is a battery, there is no need for control to transmit information about the remaining battery charge to the indoor unit control unit when the outdoor unit has finished operating. This makes it possible to easily grasp the charge level of the battery without complicating the control.

In the air conditioner according to embodiment 4, the outdoor unit control unit may be configured to be started when the voltage of the DC bus to which the DC power source is connected reaches a specified voltage. In this configuration, if the DC power source is a battery, battery power is not consumed when the air conditioner is not operating, and the battery power can be used effectively. Even with this configuration, if information about the remaining battery charge is transmitted to the indoor unit control unit when the outdoor unit ends operation, the information about the remaining battery charge can be promptly received from the indoor unit control unit after the outdoor unit control unit is started, making it possible to reliably grasp the amount of charge in the battery.

In the above embodiment, an air conditioner has been described as an example, but the invention can also be applied to heat pump water heaters, refrigerators, freezers, and other refrigeration cycle devices similar to air conditioners.

In addition, the configurations shown in the above embodiments are merely examples, and may be combined with other known technologies, or the embodiments may be combined with each other. In addition, parts of the configurations may be omitted or modified without departing from the spirit of the invention.

10 AC power supply, 20 indoor unit, 21 indoor unit board, 22, 51 rectification unit, 23 indoor unit control unit, 24 indoor unit actuator, 25, 91 AC switch, 30 communication line, 31 power line, 32 DC power line, 40 outdoor unit, 50 outdoor unit board, 52, 53 inverter, 54 outdoor unit control unit, 56 DC busbar, 60 compressor, 70 outdoor unit fan, 80 battery, 82 DC/DC converter, 90 outdoor unit actuator, 92 DC switch, 100 air conditioner, 200 processor, 202 memory.

Claims

an indoor unit to which an AC power supply voltage is applied from an AC power supply;
an outdoor unit electrically connected to the indoor unit by a communication line and at least one power line;
an AC switch for applying the AC power supply voltage from the indoor unit to the outdoor unit;
A DC power source that is connectable to the outdoor unit and capable of charge/discharge and step-up/step-down control;
Equipped with
the outdoor unit includes an outdoor unit load that operates by receiving both or either one of a first DC power supply voltage obtained by rectifying the AC power supply voltage and a second DC power supply voltage applied from the DC power supply.
an outdoor unit to which an AC power supply voltage is applied from an AC power supply;
an indoor unit electrically connected to the outdoor unit by a communication line and at least one power line;
an AC switch for applying the AC power supply voltage from the outdoor unit to the indoor unit;
A DC power source that is connectable to the outdoor unit and capable of charge/discharge and step-up/step-down control;
Equipped with
the outdoor unit includes an outdoor unit load that operates by receiving both or either one of a first DC power supply voltage obtained by rectifying the AC power supply voltage and a second DC power supply voltage applied from the DC power supply.
An outdoor unit control unit that controls the operation of the outdoor unit,
The air conditioner according to claim 1 or 2, wherein the second DC power supply voltage is constantly applied to the outdoor unit control unit.
An outdoor unit control unit that controls the operation of the outdoor unit,
The air conditioner according to claim 1 or 2, wherein the outdoor unit control unit is activated when a voltage of a DC bus to which the DC power supply is connected reaches a specified voltage.
The air conditioner according to claim 1 , further comprising a DC switch for applying the second DC power supply voltage to the indoor unit.
The air conditioner according to claim 5 , wherein, when the air conditioner is in an AC non-receiving operation in which the air conditioner operates without receiving the AC power supply voltage, the DC switch is closed to apply the second DC power supply voltage to the indoor unit.
The air conditioner according to claim 6 , wherein the AC non-receiving operation occurs when a power outage occurs in the AC power source.
The air conditioner according to claim 6 , wherein the AC non-receiving operation is performed when a demand response request is issued to the air conditioner.
The air conditioner according to claim 8 , wherein the amount of power supplied from the DC power supply is adjusted based on the demand response request.
an outdoor unit to which an AC power supply voltage is applied from an AC power supply;
an indoor unit electrically connected to the outdoor unit by at least a communication line;
A DC power source that is connectable to the outdoor unit and capable of charge/discharge and step-up/step-down control;
Equipped with
The outdoor unit includes:
an outdoor unit load that operates by receiving both or either one of a first DC power supply voltage obtained by rectifying the AC power supply voltage and a second DC power supply voltage applied from the DC power supply;
a DC power supply line electrically connecting a DC busbar of the outdoor unit to which the DC power supply is connected and the indoor unit;
a DC switch for applying the first DC power supply voltage and the second DC power supply voltage to the indoor unit;
An air conditioner equipped with:
An outdoor unit control unit that controls the operation of the outdoor unit,
The air conditioner according to claim 10 , wherein the second DC power supply voltage is constantly applied to the outdoor unit control unit.
An outdoor unit control unit that controls the operation of the outdoor unit,
The air conditioner according to claim 10, wherein the outdoor unit control unit is activated when the voltage of the DC bus reaches a specified voltage.
The outdoor unit includes an outdoor unit fan,
The air conditioner according to claim 1 , wherein the DC power supply is charged when the outdoor unit fan is rotated by an external force.