Air conditioning system, control method and control device of air conditioning system and storage medium

Abstract

The invention provides an air conditioning system, a control method and device of the air conditioning system and a storage medium. The air conditioner comprises a direct current port electrically connected with a motor loop of the air conditioner and an alternating current port electrically connected with a control loop of the air conditioner; a DC power supply device configured to be electrically connected with the DC / DC converter; the direct current bus is configured to be electrically connected with the DC / DC converter and the direct current port so as to provide direct current for the direct current port; the energy storage converter comprises a first port connected with a power grid through a switch and a second port electrically connected with the direct current bus, and the first port is electrically connected with the alternating current port; a detection device configured to detect a bus voltage of the DC bus; and the control device is configured to judge whether the power grid is powered down or not according to the bus voltage, control the on-off state of the switch and the working mode of the energy storage converter according to the judgment result, and provide alternating current for the alternating current port.

Description

Technical Field

[0001] The present disclosure relates to the technical field of air conditioning, and in particular to an air conditioning system and a control method thereof, a control device and a storage medium. Background Art

[0002] In the existing photovoltaic energy storage air conditioning system, the direct current provided by the photovoltaic equipment and the energy storage equipment is converted into alternating current through the DC (Direct Current) / AC (Alternating Current) converter, and then the alternating current is provided to the air conditioner. Since the DC / AC converter will cause energy conversion loss, the efficiency of the energy generated by the photovoltaic equipment and the energy storage equipment is reduced.

[0003] In order to solve this problem, one method currently used is to convert the air conditioner into a DC power source, that is, to set a DC port for the air conditioner so that the air conditioner can directly use the DC power provided by the photovoltaic device and the energy storage device through the DC port. Summary of the invention

[0004] The inventors noticed that in the related art, in order to avoid the energy loss caused by converting DC power into AC power, the air conditioner is converted into DC power. However, the conversion of the air conditioner into DC power is relatively complicated and costly, and the air conditioner after the conversion into DC power is not very versatile and cannot use both DC power and AC power at the same time.

[0005] Accordingly, the present disclosure provides an air conditioning system, by setting a DC interface and an AC interface for the air conditioner, the DC port is electrically connected to the motor circuit of the air conditioner, and the AC port is electrically connected to the control circuit of the air conditioner, that is, in the air conditioner, only the motor circuit uses DC power, while other control circuits still use AC power, so that without large-scale modification of the air conditioner, the air conditioner can use DC power and AC power at the same time, thereby improving the versatility of the air conditioner. At the same time, the air conditioning system of the present disclosure can switch between the grid-connected state and the off-grid state, and can still provide AC power to the AC port of the air conditioner in the off-grid state, thereby ensuring the normal operation of the air conditioner.

[0006] According to a first aspect of an embodiment of the present disclosure, there is provided an air conditioning system, comprising: an air conditioner, comprising a DC port electrically connected to a motor circuit of the air conditioner, and an AC port electrically connected to a control circuit of the air conditioner; a DC power supply device, configured to be electrically connected to a DC / DC converter; a DC bus, configured to be electrically connected to the DC / DC converter and the DC port, so as to provide DC power to the DC port; an energy storage inverter, comprising a first port connected to a power grid through a switch, and a second port electrically connected to the DC bus, wherein the first port is electrically connected to the AC port; a detection device, configured to detect a bus voltage of the DC bus; and a control device, configured to determine whether the power grid is powered off based on the bus voltage, and to control the switching state of the switch and the working mode of the energy storage inverter based on the determination result, so as to provide AC power to the AC port.

[0007] In some embodiments, the control device is configured to: when it is determined based on the bus voltage that the power grid is not powered off, control the switch to be in a closed state so as to provide the AC power provided by the power grid to the AC port, and control the energy storage inverter to be in a first operating mode, wherein in the first operating mode, the energy storage inverter receives the AC power provided by the power grid through the first port, and provides DC power to the DC bus through the second port.

[0008] In some embodiments, the control device is configured to control the DC / DC converter to be in current mode when the power grid is not powered off.

[0009] In some embodiments, the control device is configured to: when it is determined that the power grid is powered off based on the bus voltage, control the switch to be in an on state, and control the energy storage inverter to be in a second operating mode, wherein in the second operating mode, the energy storage inverter receives DC power provided by the DC bus through the second port, and provides AC power to the AC port through the first port.

[0010] In some embodiments, the control device is configured to: when it is determined that the power grid is powered off, control the DC / DC converter to be in a voltage mode.

[0011] In some embodiments, the detection device is configured to detect the voltage of the power grid; the control device is configured to determine whether the voltage of the power grid is greater than a voltage threshold when the switch is in the on state; when the voltage of the power grid is greater than the voltage threshold, the switch is controlled to be in a closed state so as to provide the AC power provided by the power grid to the AC port, and control the energy storage inverter to be in the first operating mode.

[0012] In some embodiments, the control device is configured to: when the voltage of the power grid is greater than the voltage threshold, control the energy storage inverter to adjust the electrical parameters of the alternating current output through the first port; when the electrical parameters of the alternating current output by the energy storage inverter through the first port are consistent with the electrical parameters of the alternating current provided by the power grid, control the switch to be in a closed state and control the energy storage inverter to be in the first operating mode.

[0013] In some embodiments, the electrical parameter of the alternating current includes at least one of the frequency, amplitude and phase of the alternating current.

[0014] In some embodiments, the control device is configured to: determine whether the voltage drop slope of the DC bus is less than a slope threshold, and determine that the power grid is not powered off when the voltage drop slope of the DC bus is less than the slope threshold; and determine that the power grid is powered off when the voltage drop slope of the DC bus is greater than or equal to the slope threshold.

[0015] In some embodiments, the DC power supply device includes at least one of a photovoltaic device and an energy storage device.

[0016] In some embodiments, the energy storage device is configured to store direct current output by the photovoltaic device.

[0017] According to a second aspect of an embodiment of the present disclosure, there is provided an air-conditioning system control method, which is applied to a control device in an air-conditioning system described in any of the above embodiments, the control method comprising: judging whether a power grid is powered off based on a bus voltage of a DC bus in the air-conditioning system; and controlling a switching state of a switch in the air-conditioning system and an operating mode of an energy storage inverter in the air-conditioning system based on a judgment result, so as to provide AC power to an AC port of an air conditioner in the air-conditioning system, wherein the DC bus provides DC power to a DC port of the air conditioner.

[0018] In some embodiments, controlling the switching state of the switch in the air-conditioning system and the working mode of the energy storage inverter in the air-conditioning system according to the judgment result includes: when it is determined according to the bus voltage that the power grid is not powered off, controlling the switch to be in a closed state so as to provide the AC power provided by the power grid to the AC port; controlling the energy storage inverter to be in a first working mode, wherein in the first working mode, the energy storage inverter receives the AC power provided by the power grid through the first port, and provides DC power to the DC bus through the second port.

[0019] In some embodiments, when the power grid is not powered off, the DC / DC converter is controlled to be in current mode.

[0020] In some embodiments, controlling the switching state of the switch in the air-conditioning system and the working mode of the energy storage inverter in the air-conditioning system according to the judgment result includes: controlling the switch to be in an on state when it is determined that the power grid is powered off according to the bus voltage; controlling the energy storage inverter to be in a second working mode, wherein in the second working mode, the energy storage inverter receives DC power provided by the DC bus through the second port, and provides AC power to the AC port through the first port.

[0021] In some embodiments, when it is determined that the grid loses power, the DC / DC converter is controlled to be in a voltage mode.

[0022] In some embodiments, when the switch is in the on state, it is determined whether the voltage of the power grid is greater than a voltage threshold; when the voltage of the power grid is greater than the voltage threshold, the switch is controlled to be in a closed state so that the AC power provided by the power grid is provided to the AC port; and the energy storage inverter is controlled to be in the first operating mode.

[0023] In some embodiments, when the voltage of the power grid is greater than the voltage threshold, controlling the switch to be in a closed state includes: when the voltage of the power grid is greater than the voltage threshold, controlling the energy storage inverter to adjust the electrical parameters of the alternating current output through the first port; when the electrical parameters of the alternating current output by the energy storage inverter through the first port are consistent with the electrical parameters of the alternating current provided by the power grid, controlling the switch to be in a closed state.

[0024] In some embodiments, the electrical parameter of the alternating current includes at least one of the frequency, amplitude and phase of the alternating current.

[0025] In some embodiments, the determining whether the power grid has lost power includes: determining whether the voltage drop slope of the DC bus is less than a slope threshold; determining that the power grid has not lost power when the voltage drop slope of the DC bus is less than the slope threshold; determining that the power grid has lost power when the voltage drop slope of the DC bus is greater than or equal to the slope threshold.

[0026] According to a third aspect of an embodiment of the present disclosure, a control device is provided, comprising: a memory; and a processor coupled to the memory, the processor being configured to execute an air conditioning system control method as described in any of the above embodiments based on instructions stored in the memory.

[0027] According to a fourth aspect of an embodiment of the present disclosure, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores computer instructions, and when the instructions are executed by a processor, the air-conditioning system control method as described in any of the above embodiments is implemented.

[0028] According to a fifth aspect of an embodiment of the present disclosure, there is provided a computer program product, comprising computer instructions, wherein when the computer instructions are executed by a processor, the air conditioning system control method as described in any of the above embodiments is implemented.

[0029] Other features and advantages of the present disclosure will become apparent from the following detailed description of exemplary embodiments of the present disclosure with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0031] Figure 1 A schematic diagram of the structure of an air conditioning system according to an embodiment of the prior art;

[0032] Figure 2 It is a structural schematic diagram of an air conditioning system of another embodiment in the prior art;

[0033] Figure 3 This is a schematic structural diagram of an air conditioning system according to an embodiment of the present disclosure;

[0034] Figure 4 It is a structural schematic diagram of an air conditioning system according to another embodiment of the present disclosure;

[0035] Figure 5 A schematic diagram of a flow chart of an air conditioning system control method according to an embodiment of the present disclosure;

[0036] Figure 6 A flowchart of an air conditioning system control method according to another embodiment of the present disclosure;

[0037] Figure 7 The figure is a schematic diagram of the structure of a control device according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present disclosure to clearly and completely describe the technical solutions in the embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, rather than all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present disclosure and its application or use. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0039] The relative arrangement of components and steps, the numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present disclosure unless specifically stated otherwise.

[0040] At the same time, it should be understood that for the convenience of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship.

[0041] Technologies, methods, and apparatus known to ordinary technicians in the relevant field may not be discussed in detail, but where appropriate, such technologies, methods, and apparatus should be considered part of the authorization specification.

[0042] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0043] It should be noted that like reference numerals and letters refer to similar items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0044] Figure 1 The figure is a schematic diagram of the structure of an air conditioning system according to an embodiment of the prior art.

[0045] like Figure 1 As shown, the direct current generated by the photovoltaic device 11 is converted into alternating current by the DC / AC converter 12, and the direct current generated by the energy storage device 13 is converted into alternating current by the DC / AC converter 14. Thus, the alternating current provided by the power grid 15, the alternating current provided by the DC / AC converter 12, and the DC / AC converter 13 are provided to the air conditioner 16.

[0046] Since the DC / AC converters 12 and 13 may cause energy conversion losses, the utilization efficiency of the energy generated by the photovoltaic device 11 and the energy storage device 13 is reduced.

[0047] Figure 2 It is a structural schematic diagram of an air conditioning system of another embodiment in the prior art.

[0048] like Figure 2As shown, by converting the air conditioner 25 to DC, the air conditioner 25 has a DC interface. The DC power generated by the photovoltaic device 21 and the energy storage device 22 can be directly provided to the air conditioner 25 through the DC interface. At the same time, the AC power provided by the power grid 23 is converted into DC power through the rectifier power module unit and is also provided to the air conditioner 25 through the DC interface.

[0049] Since the conversion of air conditioners to DC is relatively complex and costly, and the air conditioners after the conversion are not very versatile and cannot use both DC and AC power at the same time.

[0050] Accordingly, the present disclosure provides an air conditioning system, by setting a DC interface and an AC interface for the air conditioner, the DC port is electrically connected to the motor circuit of the air conditioner, and the AC port is electrically connected to the control circuit of the air conditioner, that is, in the air conditioner, only the motor circuit uses DC power, while other control circuits still use AC power, so that without large-scale modification of the air conditioner, the air conditioner can use DC power and AC power at the same time, thereby improving the versatility of the air conditioner. At the same time, the air conditioning system of the present disclosure can switch between the grid-connected state and the off-grid state, and can still provide AC power to the AC port of the air conditioner in the off-grid state, thereby ensuring the normal operation of the air conditioner.

[0051] Figure 3 The present invention is a schematic structural diagram of an air conditioning system according to an embodiment of the present invention.

[0052] like Figure 3 As shown, the air conditioning system includes a DC bus 30, an air conditioner 31, a DC power supply device 32, a DC / DC converter 33, a power storage converter (Power Conversion System, PCS for short) 34 and a switch K.

[0053] The air conditioner 31 includes a DC port 311 electrically connected to a motor circuit 312 of the air conditioner, and an AC port 313 electrically connected to a control circuit 314 of the air conditioner.

[0054] For example, the control circuit 314 of the air conditioner includes an AC mainboard power supply circuit, an AC valve component power supply circuit, and the like.

[0055] The DC power supply device 32 is configured to be electrically connected to the DC / DC converter 33 .

[0056] For example, the DC power supply device 32 includes at least one of a photovoltaic device and an energy storage device, so that both the photovoltaic device and the energy storage device can provide DC power to the air conditioner 31 through the DC bus 30. For example, when the photovoltaic device cannot operate normally, the energy storage device can continue to provide DC power to the air conditioner 31 through the DC bus 30, thereby ensuring that the DC bus 30 can be in a stable state and improving the stability of the air conditioner operation.

[0057] The DC bus 30 is configured to be electrically connected to the DC / DC converter 33 and the DC port 311 so as to provide DC power to the DC port 311. Thus, the motor circuit 312 in the air conditioner 31 can be ensured to operate normally.

[0058] The energy storage converter 34 includes a first port 341 connected to the power grid 35 via a switch K, and a second port 342 electrically connected to the DC bus 30. The first port 341 is electrically connected to the AC port 313;

[0059] The detection device 36 is configured to detect the bus voltage of the DC bus 30 .

[0060] The control device 37 is configured to determine whether the power grid 35 is powered off according to the bus voltage, and control the switching state of the switch K and the working mode of the energy storage converter 34 according to the determination result to provide AC power to the AC port.

[0061] It should be noted that, in the first working mode, the energy storage converter 34 receives the AC power provided by the power grid through the first port 341, and provides the DC power to the DC bus 30 through the second port 342. In the second working mode, the energy storage converter 34 receives the DC power provided by the DC bus 30 through the second port 342, and provides the AC power to the AC port 313 through the first port 341.

[0062] No matter the energy storage converter 34 is in the first working mode or the second working mode, it can provide AC power to the AC interface 313 of the air conditioner 31 , thereby ensuring the normal operation of the control loop 314 of the air conditioner.

[0063] In the air conditioning system provided by the above embodiment of the present disclosure, the air conditioning is provided with a DC port and an AC port, the DC port is electrically connected to the motor circuit, and the AC port is electrically connected to the control circuit, and by providing DC to the DC port and AC to the AC port, it is ensured that photovoltaic and grid power supply can be effectively utilized without large-scale DC transformation of the air conditioning. In addition, by setting a switch and an energy storage converter in the air conditioning system, it is possible to provide AC power to the AC port of the air conditioning by adjusting the state of the switch and the energy storage converter regardless of whether the grid has electricity, thereby ensuring the normal operation of the DC load and AC load of the air conditioning.

[0064] In some embodiments, the control device 37 is configured to: determine whether the voltage drop slope of the DC bus 30 is less than the slope threshold, and determine that the power grid is not powered off when the voltage drop slope of the DC bus 30 is less than the slope threshold. If the voltage drop slope of the DC bus 30 is greater than or equal to the slope threshold, determine that the power grid is powered off.

[0065] It should be noted here that the DC bus usually has voltage fluctuations. If the power grid is directly judged to be powered off when the voltage of the DC bus is low, it is easy to cause misjudgment. Since the voltage drop slope of the DC bus can accurately reflect the current situation of the DC bus, judging whether the power grid is powered off based on the voltage drop slope of the DC bus can accurately detect the current voltage change of the DC bus, thereby effectively avoiding misjudgment caused by direct voltage detection.

[0066] Specifically, under normal circumstances, the voltage on the DC bus fluctuates to a certain extent. When the power grid can continuously provide power to the DC bus, the voltage fluctuation on the DC bus is small. If the power grid loses power, the grid cannot continue to provide power to the DC bus. In this case, the voltage on the DC bus will drop rapidly in a short period of time, and the voltage drop will be large. Therefore, the voltage drop slope can effectively determine whether the power grid has lost power.

[0067] In some embodiments, the control device 37 is configured to: when it is determined based on the bus voltage that the power grid 35 is not powered off, control the switch K to be in a closed state so as to provide the AC power provided by the power grid 35 to the AC port 313, and control the energy storage inverter 34 to be in the first working mode.

[0068] That is to say, when the power grid 35 is not powered off, the DC power supply device 32 and the energy storage converter 34 provide DC power to the DC bus 30, and the DC bus 30 provides DC power to the DC interface 311. The power grid 35 directly provides AC power to the AC port 313. Thus, the air conditioner 31 receives the DC power provided by the DC power supply device 32 and the energy storage converter 34 through the DC port 311, and receives the AC power provided by the power grid 35 through the AC port 313. Thus, the motor circuit and the control circuit of the air conditioner 31 can operate normally.

[0069] In some embodiments, the control device 37 is configured to control the DC / DC converter to be in the current mode when the power grid 35 is not powered off.

[0070] It should be noted here that if the DC / DC converter 33 is in current mode, the current stability of the DC bus can be ensured, that is, the required current can be provided to the motor circuit 312. Even if the DC load changes, the DC / DC converter 33 can meet the current demand of the DC load, so that the motor circuit 312 can operate normally.

[0071] In some embodiments, the control device 37 is configured to: when it is determined according to the bus voltage that the power grid 35 is powered off, control the switch K to be in an on state, and control the energy storage converter 34 to be in the second working mode.

[0072] That is, when the power grid 35 loses power, the DC power supply device 32 provides DC power to the DC bus 30, so that the air conditioner 31 receives the DC power provided by the DC power supply device 32 through the DC port 311. The energy storage converter 34 receives the DC power provided by the DC bus 30 through the second port 342, and provides AC power to the AC port 313 through the first port 341. Therefore, when the power grid 35 loses power, the motor circuit and the control circuit of the air conditioner 31 can operate normally.

[0073] In some embodiments, the control device 37 is configured to: when it is determined that the power grid 35 is powered off, control the DC / DC converter 33 to be in the voltage mode.

[0074] It should be noted that if the DC / DC converter 33 is in voltage mode, the voltage of the DC bus can be stabilized, so that the AC interface receives AC power with a stable voltage, thereby ensuring that the AC load in the control loop 314 can operate normally. Provide the required current for the motor loop 312,

[0075] In some embodiments, the detection device 36 is configured to detect the voltage of the power grid 35 .

[0076] The control device 37 is configured to determine whether the voltage of the power grid 35 is greater than the voltage threshold when the switch K is in the open state. When the voltage of the power grid 35 is greater than the voltage threshold, the switch K is controlled to be in the closed state so as to provide the AC power provided by the power grid 35 to the AC port 313, and control the energy storage converter 34 to be in the first working mode.

[0077] That is to say, when the power grid 35 loses power, the switch K is in the open state, and the energy storage converter 34 is in the second working mode, that is, the air conditioning system is in the off-grid mode. In the off-grid mode, the electric energy used by the air conditioner 31 comes from the DC power supply device 32. If the voltage of the power grid 35 returns to normal, the control device 37 controls the switch K to be in the closed state, and controls the energy storage converter 34 to be in the first working mode, that is, the air conditioning system switches from the off-grid mode to the grid-connected mode. In the grid-connected mode, the AC power used by the air conditioner 31 comes from the power grid, and the DC power used by the air conditioner 31 comes from the power grid and the DC power supply device 32. Since the control device 37 can conveniently and quickly switch the air conditioning system from the off-grid mode to the grid-connected mode, the power grid 35 can be effectively used to power the air conditioner 31, thereby ensuring the normal operation of the air conditioner 31.

[0078] In some embodiments, the control device 37 is configured to: when the voltage of the power grid 35 is greater than the voltage threshold, control the energy storage converter 34 to adjust the electrical parameters of the alternating current output through the first port 341. When the electrical parameters of the alternating current output by the energy storage converter 34 through the first port 341 are consistent with the electrical parameters of the alternating current provided by the power grid 35, the switch K is controlled to be in a closed state, and the energy storage converter 34 is controlled to be in the first working mode.

[0079] It should be noted here that after the power grid 35 returns to normal, the relevant electrical parameters of the AC power output by the energy storage inverter 34 are adjusted first. When the relevant electrical parameters of the AC power output by the energy storage inverter 34 are consistent with the relevant electrical parameters of the AC power provided by the power grid, the off-grid mode is switched to the grid-connected mode to avoid damage to the AC load in the control loop 314 due to changes in the AC power provided to the AC port 313.

[0080] For example, the electrical parameter of the alternating current includes at least one of the frequency, amplitude, and phase of the alternating current.

[0081] It should be noted here that in the process of switching from the off-grid mode to the grid-connected mode, the output of the energy storage inverter 34 is adjusted so that the frequency, amplitude and phase of the AC power output by the energy storage inverter 34 are the same as the frequency, amplitude and phase of the AC power provided by the power grid. This ensures that after switching from the off-grid mode to the grid-connected mode, the AC load in the control loop 314 will not be damaged due to changes in the frequency, amplitude and phase of the AC power, thereby effectively extending the service life of the AC load.

[0082] Figure 4 It is a structural schematic diagram of an air conditioning system according to another embodiment of the present disclosure.

[0083] Compared to Figure 3 In the embodiment shown, Figure 4 In the illustrated embodiment, the DC power supply device 32 includes a photovoltaic device 321 and an energy storage device 322. Accordingly, the DC / DC converter 33 includes a DC / DC converter 331 electrically connected to the photovoltaic device 321, and a DC / DC converter 332 electrically connected to the energy storage device 322.

[0084] For the sake of simplicity, Figure 4 The control device 37 is not shown.

[0085] In some embodiments, the energy storage device 322 is configured to store direct current output by the photovoltaic device 321 .

[0086] For example, the photovoltaic device 321 cannot work normally due to weather reasons. In this case, the energy storage device 322 can use the stored electric energy to provide DC power to the DC bus so that the motor circuit 312 of the air conditioner 31 can operate normally.

[0087] Figure 5 The flowchart of the air conditioning system control method according to one embodiment of the present disclosure is shown in FIG. 1. In some embodiments, the following air conditioning system control method is executed by a control device in the air conditioning system, and includes steps 51-52.

[0088] In step 51, it is determined whether the power grid is powered off based on the bus voltage of the DC bus in the air conditioning system.

[0089] In some embodiments, it is determined whether the voltage drop slope of the DC bus is less than a slope threshold. If the voltage drop slope of the DC bus is less than the slope threshold, it is determined that the power grid is not powered off. If the voltage drop slope of the DC bus is greater than or equal to the slope threshold, it is determined that the power grid is powered off.

[0090] It should be noted here that the DC bus usually has voltage fluctuations. If the power grid is directly judged to be powered off when the voltage of the DC bus is low, it is easy to cause misjudgment. Since the voltage drop slope of the DC bus can accurately reflect the current situation of the DC bus, judging whether the power grid is powered off based on the voltage drop slope of the DC bus can accurately detect the current voltage change of the DC bus, thereby effectively avoiding misjudgment caused by direct voltage detection.

[0091] In step 52, based on the judgment result, the switching state of the switch in the air-conditioning system and the working mode of the energy storage inverter in the air-conditioning system are controlled to provide AC power to the AC port of the air conditioner in the air-conditioning system, wherein the DC bus provides DC power to the DC port of the air conditioner.

[0092] It should be noted here that Figure 1 As shown, in the first working mode, the energy storage converter 34 receives the AC power provided by the power grid through the first port 341, and provides the DC power to the DC bus 30 through the second port 342. In the second working mode, the energy storage converter 34 receives the DC power provided by the DC bus 30 through the second port 342, and provides the AC power to the AC port 313 through the first port 341.

[0093] No matter the energy storage converter 34 is in the first working mode or the second working mode, it can provide AC power to the AC interface 313 of the air conditioner 31 , thereby ensuring the normal operation of the control loop 314 of the air conditioner.

[0094] In the air conditioning system control method provided in the above embodiment of the present disclosure, according to whether the current power grid is powered off, the state of the switch and the energy storage converter is adjusted to provide AC power to the AC port of the air conditioner, thereby ensuring the normal operation of the AC load of the air conditioner. In addition, the DC bus provides DC power to the DC port of the air conditioner. This ensures that photovoltaic and power grid power are effectively utilized without the need for large-scale DC transformation of the air conditioner, thereby ensuring the normal operation of the DC load and AC load of the air conditioner.

[0095] In some embodiments, when it is determined according to the bus voltage that the grid is not powered off, the switch is controlled to be in a closed state so as to provide the AC power provided by the grid to the AC port, and the energy storage converter is controlled to be in the first working mode.

[0096] That is to say, Figure 1 As shown, when the power grid 35 is not powered off, the DC power supply device 32 and the energy storage converter 34 provide DC power to the DC bus 30, and the DC bus 30 provides DC power to the DC interface 311. The power grid 35 directly provides AC power to the AC port 313. As a result, the air conditioner 31 receives the DC power provided by the DC power supply device 32 and the energy storage converter 34 through the DC port 311, and receives the AC power provided by the power grid 35 through the AC port 313. As a result, the motor circuit and the control circuit of the air conditioner 31 can operate normally.

[0097] In some embodiments, when the power grid is not powered off, the DC / DC converter is controlled to be in current mode.

[0098] It should be noted here that Figure 1 As shown, if the DC / DC converter 33 is in current mode, the current of the DC bus can be ensured to be stable, that is, the required current can be provided to the motor circuit 312. Even if the DC load changes, the DC / DC converter 33 can meet the current demand of the DC load, so that the motor circuit 312 can operate normally.

[0099] In some embodiments, when it is determined that the grid is powered off according to the bus voltage, the switch is controlled to be in an on state, and the energy storage converter is controlled to be in a second working mode.

[0100] That is to say, Figure 1 As shown, when the power grid 35 loses power, the DC power supply device 32 provides DC power to the DC bus 30, so that the air conditioner 31 receives the DC power provided by the DC power supply device 32 through the DC port 311. The energy storage converter 34 receives the DC power provided by the DC bus 30 through the second port 342, and provides AC power to the AC port 313 through the first port 341. Therefore, when the power grid 35 loses power, the motor circuit and the control circuit of the air conditioner 31 can operate normally.

[0101] In some embodiments, when it is determined that the grid is powered off, the DC / DC converter is controlled to be in a voltage mode.

[0102] It should be noted that if the DC / DC converter 33 is in voltage mode, the voltage of the DC bus can be stabilized, so that the AC interface receives AC power with a stable voltage, thereby ensuring that the AC load in the control loop 314 can operate normally. Provide the required current for the motor loop 312,

[0103] In some embodiments, when the switch is in an open state, it is determined whether the voltage of the power grid is greater than a voltage threshold. When the voltage of the power grid is greater than the voltage threshold, the switch is controlled to be in a closed state so as to provide the AC power provided by the power grid to the AC port, and the energy storage converter is controlled to be in the first working mode.

[0104] That is to say, Figure 1 As shown, when the power grid 35 loses power, the switch K is in the open state, and the energy storage converter 34 is in the second working mode, that is, the air conditioning system is in the off-grid mode. If the voltage of the power grid 35 returns to normal, the control device 37 controls the switch K to be in the closed state, and controls the energy storage converter 34 to be in the first working mode, that is, the air conditioning system switches from the off-grid mode to the grid-connected mode. Since the control device 37 can conveniently and quickly switch the air conditioning system from the off-grid mode to the grid-connected mode, the power grid 35 can be effectively used to power the air conditioner 31, ensuring the normal operation of the air conditioner 31.

[0105] In some embodiments, when the voltage of the power grid is greater than a voltage threshold, the energy storage converter is controlled to adjust the electrical parameters of the alternating current output through the first port. When the electrical parameters of the alternating current output by the energy storage converter through the first port are consistent with the electrical parameters of the alternating current provided by the power grid, the control switch is in a closed state.

[0106] It should be noted here that after the power grid 35 returns to normal, the relevant electrical parameters of the AC power output by the energy storage inverter 34 are adjusted first. When the relevant electrical parameters of the AC power output by the energy storage inverter 34 are consistent with the relevant electrical parameters of the AC power provided by the power grid, the off-grid mode is switched to the grid-connected mode to avoid damage to the AC load in the control loop 314 due to changes in the AC power provided to the AC port 313.

[0107] For example, the electrical parameter of the alternating current includes at least one of the frequency, amplitude, and phase of the alternating current.

[0108] It should be noted here that in the process of switching from the off-grid mode to the grid-connected mode, the output of the energy storage inverter 34 is adjusted so that the frequency, amplitude and phase of the AC power output by the energy storage inverter 34 are the same as the frequency, amplitude and phase of the AC power provided by the power grid. This ensures that after switching from the off-grid mode to the grid-connected mode, the AC load in the control loop 314 will not be damaged due to changes in the frequency, amplitude and phase of the AC power, thereby effectively extending the service life of the AC load.

[0109] Figure 6 FIG. 6 is a flow chart of an air conditioning system control method according to another embodiment of the present disclosure. In some embodiments, the following air conditioning system control method is executed by a control device in the air conditioning system, and includes steps 61-68.

[0110] In step 61, it is determined whether the grid is powered off based on the bus voltage of the DC bus in the air conditioning system.

[0111] If the grid is not powered off, execute step 62. Otherwise, execute step 64.

[0112] In step 62, the switch is controlled to be in a closed state so as to provide the AC power provided by the grid to the AC port.

[0113] In step 63, the energy storage converter is controlled to be in the first operating mode, and the DC / DC converter is controlled to be in the current mode.

[0114] In this case, the air conditioning system operates in this grid-connected mode.

[0115] In step 64, the switch is controlled to be in an on state.

[0116] In step 65, the energy storage converter is controlled to be in the second operation mode, and the DC / DC converter is controlled to be in the voltage mode.

[0117] In this case, the air conditioning system operates in this off-grid mode.

[0118] In step 66, when the switch is in the on state, it is determined whether the voltage of the grid is greater than the voltage threshold, that is, it is determined whether the grid has power.

[0119] If the voltage of the grid is not greater than the voltage threshold, that is, the grid has no electricity, then return to step 64. If the voltage of the grid is greater than the voltage threshold, that is, the grid has electricity, then execute step 67.

[0120] In step 67 , the energy storage converter is controlled to adjust the electrical parameters of the AC power output through the first port.

[0121] For example, the electrical parameters of alternating current include the frequency, amplitude, and phase of the alternating current.

[0122] In step 68, it is determined whether the electrical parameters of the alternating current output by the energy storage converter through the first port are consistent with the electrical parameters of the alternating current provided by the power grid.

[0123] If the electrical parameters of the AC power outputted by the energy storage converter through the first port are inconsistent with the electrical parameters of the AC power provided by the power grid, return to step 67. If the electrical parameters of the AC power outputted by the energy storage converter through the first port are consistent with the electrical parameters of the AC power provided by the power grid, return to step 62.

[0124] That is, steps 66-68 are the switching process of the air conditioning system from the off-grid mode to the on-grid mode.

[0125] Figure 7 The figure is a schematic diagram of the structure of a control device according to an embodiment of the present disclosure.

[0126] like Figure 7 As shown, the control device 70 may be in the form of a general-purpose computing device. The control device 70 includes a memory 71, a processor 72, and a bus 73 connecting different system components.

[0127] The memory 71 may include, for example, a system memory, a non-volatile storage medium, etc. The system memory may store, for example, an operating system, an application program, a boot loader, and other programs. The system memory may include a volatile storage medium, such as a random access memory (RAM) and / or a cache memory. The non-volatile storage medium may store, for example, instructions of a corresponding embodiment of at least one billing processing method being executed. The non-volatile storage medium includes, but is not limited to, a disk memory, an optical memory, a flash memory, etc.

[0128] The processor 72 may be implemented by a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gates or transistors, and other discrete hardware components. Accordingly, each module such as an acquisition module, a calculation module, and an adjustment module may be implemented by a central processing unit (CPU) running instructions in a memory that execute corresponding steps, or may be implemented by a dedicated circuit that executes corresponding steps.

[0129] For example, the processor 72 is configured to execute instructions stored in the memory to implement the following Figure 5 and Figure 6 The method of any one of the embodiments.

[0130] The bus 73 may use any of a variety of bus structures, including, but not limited to, an Industry Standard Architecture (ISA) bus, a Micro Channel Architecture (MCA) bus, and a Peripheral Component Interconnect (PCI) bus.

[0131] The interfaces 74, 75, 76 of the control device 70, the memory 71 and the processor 72 can be connected via a bus 73. The input / output interface 74 can provide a connection interface for input / output devices such as a display, a mouse, and a keyboard. The network interface 75 provides a connection interface for various networked devices. The storage interface 76 provides a connection interface for external storage devices such as a floppy disk, a USB flash drive, and an SD card.

[0132] Here, various aspects of the present disclosure are described with reference to flowcharts and / or block diagrams of methods, devices, and computer program products according to embodiments of the present disclosure. It should be understood that each frame of the flowchart and / or block diagram and the combination of frames can be implemented by computer-readable program instructions.

[0133] These computer-readable program instructions may be provided to a processor of a general-purpose computer, a special-purpose computer or other programmable device to produce a machine, so that the processor executes the instructions to produce means for implementing the functions specified in one or more blocks in the flowchart and / or block diagram.

[0134] These computer-readable program instructions may also be stored in a computer-readable memory, which cause the computer to work in a specific manner to produce an article of manufacture, including instructions for implementing the functions specified in one or more blocks in the flowchart and / or block diagram.

[0135] The present disclosure can take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects.

[0136] The present disclosure also provides a computer-readable storage medium, wherein the computer-readable storage medium stores computer instructions, and when the instructions are executed by a processor, the following is implemented: Figure 5 and Figure 6 The method of any one of the embodiments.

[0137] The present disclosure also provides a computer program product, including computer instructions, wherein when the computer instructions are executed by a processor, the following is achieved: Figure 5 and Figure 6 The method of any one of the embodiments.

[0138] By implementing the above-mentioned embodiments of the present disclosure, the following beneficial effects can be obtained.

[0139] 1) Without the need for large-scale DC conversion of the air conditioner, the air conditioner can use both DC and AC power, thereby improving the versatility of the air conditioner.

[0140] 2) The air conditioning system of the present disclosure can switch between a grid-connected state and an off-grid state, and can still provide AC power to the AC port of the air conditioner in the off-grid state, thereby ensuring the normal operation of the air conditioner.

[0141] In some embodiments, the functional unit described above may be implemented as a general-purpose processor, a programmable logic controller (PLC), a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or any appropriate combination thereof, for performing the functions described in the present disclosure.

[0142] A person skilled in the art will understand that all or part of the steps to implement the above embodiments may be accomplished by hardware or by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, and the above-mentioned storage medium may be a read-only memory, a disk or an optical disk, etc.

[0143] The description of the present disclosure is given for the purpose of illustration and description, and is not intended to be exhaustive or to limit the present disclosure to the disclosed form. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiments are selected and described in order to better illustrate the principles and practical applications of the present disclosure, and to enable those of ordinary skill in the art to understand the present disclosure and thereby design various embodiments with various modifications suitable for specific uses.

Claims

1. An air conditioning system, comprising: An air conditioner, comprising a DC port electrically connected to a motor circuit of the air conditioner, and an AC port electrically connected to a control circuit of the air conditioner; A DC power supply device configured to be electrically connected to the DC / DC converter; a DC bus configured to be electrically connected to the DC / DC converter and the DC port so as to provide DC power to the DC port; An energy storage converter, comprising a first port connected to a power grid through a switch, and a second port electrically connected to the DC bus, wherein the first port is electrically connected to the AC port; A detection device, configured to detect a bus voltage of the DC bus; The control device is configured to determine whether the power grid is powered off according to the bus voltage, and control the switching state of the switch and the working mode of the energy storage converter according to the determination result to provide AC power to the AC port.

2. The air conditioning system according to claim 1, wherein: The control device is configured to: when it is determined according to the bus voltage that the power grid is not powered off, control the switch to be in a closed state so as to provide the AC power provided by the power grid to the AC port, and control the energy storage inverter to be in a first operating mode, wherein in the first operating mode, the energy storage inverter receives the AC power provided by the power grid through the first port, and provides DC power to the DC bus through the second port.

3. The air conditioning system according to claim 2, wherein: The control device is configured to control the DC / DC converter to be in a current mode when the power grid is not powered off.

4. The air conditioning system according to claim 1, wherein: The control device is configured to: when it is determined that the power grid is powered off according to the bus voltage, control the switch to be in an on state, and control the energy storage inverter to be in a second operating mode, wherein in the second operating mode, the energy storage inverter receives DC power provided by the DC bus through the second port, and provides AC power to the AC port through the first port.

5. The air conditioning system according to claim 4, wherein: The control device is configured to: when it is determined that the power grid is powered off, control the DC / DC converter to be in a voltage mode.

6. The air conditioning system according to claim 4, wherein: The detection device is configured to detect the voltage of the power grid; The control device is configured to determine whether the voltage of the power grid is greater than a voltage threshold when the switch is in the on state; When the voltage of the power grid is greater than the voltage threshold, the switch is controlled to be in a closed state so as to provide the AC power provided by the power grid to the AC port, and the energy storage converter is controlled to be in the first working mode.

7. The air conditioning system according to claim 6, wherein: The control device is configured to: when the voltage of the power grid is greater than the voltage threshold, control the energy storage inverter to adjust the electrical parameters of the alternating current output through the first port; when the electrical parameters of the alternating current output by the energy storage inverter through the first port are consistent with the electrical parameters of the alternating current provided by the power grid, control the switch to be in a closed state and control the energy storage inverter to be in the first operating mode.

8. The air conditioning system according to claim 7, wherein: The electrical parameter of the alternating current includes at least one of the frequency, amplitude and phase of the alternating current.

9. The air conditioning system according to any one of claims 1 to 8, wherein: The control device is configured to: determine whether the voltage drop slope of the DC bus is less than a slope threshold, and determine that the power grid is not powered off when the voltage drop slope of the DC bus is less than the slope threshold; and determine that the power grid is powered off when the voltage drop slope of the DC bus is greater than or equal to the slope threshold.

10. The air conditioning system according to any one of claims 1 to 8, wherein: The DC power supply device includes at least one of a photovoltaic device and an energy storage device.

11. The air conditioning system according to claim 10, wherein: The energy storage device is configured to store direct current output by the photovoltaic device.

12. A method for controlling an air conditioning system, applied to a control device in an air conditioning system according to any one of claims 1 to 10, the method comprising: Determining whether the power grid is powered off based on the bus voltage of the DC bus in the air conditioning system; According to the judgment result, the switching state of the switch in the air-conditioning system and the working mode of the energy storage inverter in the air-conditioning system are controlled to provide AC power to the AC port of the air conditioner in the air-conditioning system, wherein the DC bus provides DC power to the DC port of the air conditioner.

13. The air conditioning system control method according to claim 12, wherein: According to the judgment result, controlling the switch state of the switch in the air-conditioning system and the working mode of the energy storage converter in the air-conditioning system includes: When it is determined according to the bus voltage that the power grid is not powered off, controlling the switch to be in a closed state so as to provide the AC power provided by the power grid to the AC port; The energy storage converter is controlled to be in a first working mode, wherein in the first working mode, the energy storage converter receives AC power provided by the power grid through the first port, and provides DC power to the DC bus through the second port.

14. The air conditioning system control method according to claim 13, further comprising: When the power grid is not powered off, the DC / DC converter is controlled to be in current mode.

15. The air conditioning system control method according to claim 12, wherein: According to the judgment result, controlling the switch state of the switch in the air-conditioning system and the working mode of the energy storage converter in the air-conditioning system includes: When it is determined that the power grid is powered off according to the bus voltage, controlling the switch to be in an on state; The energy storage converter is controlled to be in a second working mode, wherein in the second working mode, the energy storage converter receives direct current provided by the direct current bus through the second port, and provides alternating current to the alternating current port through the first port.

16. The air conditioning system control method according to claim 15, further comprising: When it is determined that the power grid is powered off, the DC / DC converter is controlled to be in a voltage mode.

17. The air conditioning system control method according to claim 15, further comprising: When the switch is in the on state, determining whether the voltage of the power grid is greater than a voltage threshold; When the voltage of the power grid is greater than the voltage threshold, controlling the switch to be in a closed state so as to provide the AC power provided by the power grid to the AC port; The energy storage converter is controlled to be in the first operating mode.

18. The air conditioning system control method according to claim 17, wherein: When the voltage of the power grid is greater than the voltage threshold, controlling the switch to be in a closed state includes: When the voltage of the power grid is greater than the voltage threshold, controlling the energy storage converter to adjust the electrical parameters of the alternating current output through the first port; When the electrical parameters of the alternating current output by the energy storage converter through the first port are consistent with the electrical parameters of the alternating current provided by the power grid, the switch is controlled to be in a closed state.

19. The air conditioning system control method according to claim 18, wherein: The electrical parameter of the alternating current includes at least one of the frequency, amplitude and phase of the alternating current.

20. The air conditioning system control method according to any one of claims 12 to 19, wherein: Determining whether the power grid is powered off includes: Determining whether the voltage drop slope of the DC bus is less than a slope threshold; When the voltage drop slope of the DC bus is less than the slope threshold, determining that the power grid is not powered off; When the voltage drop slope of the DC bus is greater than or equal to the slope threshold, it is determined that the power grid is powered off.

21. A control device comprising: Memory; A processor is coupled to the memory, and the processor is configured to execute the air conditioning system control method according to any one of claims 12-20 based on the instructions stored in the memory.

22. A computer-readable storage medium, wherein: The computer-readable storage medium stores computer instructions, and when the instructions are executed by the processor, the air-conditioning system control method according to any one of claims 12 to 20 is implemented.

23. A computer program product, comprising computer instructions, wherein when the computer instructions are executed by a processor, the air conditioning system control method according to any one of claims 12 to 20 is implemented.

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