Air conditioner and energy storage system

Abstract

Disclosed in the present invention are an air conditioner and an energy storage system. By means of the following design: a first heat exchanger has a first refrigerant passage and a first chilled water passage, a second heat exchanger has a second refrigerant passage and a second chilled water passage, and a third heat exchanger has a third refrigerant passage, upon receiving a start-up instruction, a controller controls, on the basis of an outdoor ambient temperature and an output liquid temperature of a target energy storage device, an operating mode of the air conditioner, the opening / closing of the second refrigerant passage, the opening / closing of the third refrigerant passage, and whether the first chilled water passage and the second chilled water passage are in communication with a coolant pipe of any energy storage device. While cooling the target energy storage device, the air conditioner of the present invention can also heat other energy storage devices, thereby meeting both cooling and heating requirements of energy storage devices, and accordingly solving the technical problem in the prior art whereby the energy storage devices cannot be cooled and heated simultaneously. In addition, heat is recovered and utilized by means of the second heat exchanger and is used for heating other energy storage devices, thereby improving the energy utilization rate.

Description

Air conditioning and energy storage systems Technical Field

[0001] This invention relates to the field of air conditioning technology, and more specifically, to an air conditioning and energy storage system. Background Technology

[0002] Typically, an energy storage cabinet contains multiple battery packs, and larger containerized energy storage cabinets may contain dozens of battery packs. The coolant lines for each battery pack are connected in parallel to the main coolant circuit.

[0003] When an energy storage air conditioner manages multiple parallel energy storage cabinets or multiple battery packs in a single cabinet, the air conditioner can only cool or heat at any given time. Therefore, the battery packs connected to the energy storage air conditioner can only cool or heat simultaneously, which leads to the following problem:

[0004] (1) It is impossible to accurately control the cooling / heating according to the actual working conditions of each battery pack. Some battery packs that do not require cooling / heating are subjected to cooling / heating.

[0005] (2) If only a few battery packs are working, all battery packs will be cooling / heating at the same time, which is a waste of effort;

[0006] (3) It cannot heat and cool at the same time. At the same time, when a normal energy storage air conditioner is cooling, the condenser dissipates heat to the outside, and this part of the energy is completely wasted.

[0007] Currently, most methods for improving the energy efficiency of energy storage air conditioners are natural heat dissipation, that is, water circulation does not cool through the air conditioning system in winter, but dissipates heat directly in the low-temperature air through the radiator, or the air conditioning system dissipates heat naturally through the circulation of refrigerant pumps without using a compressor; another method is heat recovery, mainly for the additional heat dissipation of components such as compressors, which is carried out by connecting a heat recovery unit in series. The recovery efficiency is generally relatively low, and it is mainly used for producing domestic hot water near residential areas. Technical issues

[0008] Therefore, current air conditioners cannot simultaneously cool and heat energy storage cabinets, and cannot meet the cooling and heating needs of energy storage cabinets at the same time. Moreover, the heat recovery efficiency of air conditioners is relatively low. Technical solutions

[0009] This invention provides an air conditioner that solves the technical problem in the prior art that it cannot simultaneously cool and heat energy storage devices.

[0010] To achieve the above-mentioned technical objectives, the present invention adopts the following technical solution:

[0011] Air conditioning, including:

[0012] compressor;

[0013] Four-way valve;

[0014] Throttling device;

[0015] The first heat exchanger has a first refrigerant channel and a first cold water channel; the first cold water channel is connected to the coolant pipelines of multiple energy storage devices respectively.

[0016] The second heat exchanger has a second refrigerant passage and a second cold water passage; the second cold water passage is connected to the coolant pipelines of multiple energy storage devices respectively.

[0017] The third heat exchanger has a third refrigerant passage; the third refrigerant passage is connected in parallel with the second refrigerant passage; the compressor, four-way valve, first refrigerant passage, throttling device, and second / third refrigerant passage form a refrigerant circulation loop;

[0018] The controller is configured to, upon receiving a power-on command, control the air conditioner's operating mode, the on / off state of the second refrigerant channel and the third refrigerant channel, as well as the connection or disconnection between the first cold water channel and the coolant channel of any energy storage device, and the connection or disconnection between the second cold water channel and the coolant channel of any energy storage device, based on the outdoor ambient temperature and the outlet temperature of the coolant pipeline of the target energy storage device.

[0019] In some embodiments of this application, the controller is further configured as follows:

[0020] Upon receiving the power-on command, when the outdoor ambient temperature Tao ≤ the preset ambient temperature Ts, it enters the low-temperature mode; in the low-temperature mode, it monitors the outlet temperature Two of the coolant pipeline of the target energy storage device.

[0021] When the outlet temperature Two is within the first set temperature range, it enters the low-temperature heating operation mode; in the low-temperature heating operation mode, the compressor starts, the second refrigerant channel is shut off, the third refrigerant channel is opened, the second cold water channel is shut off, and the first cold water channel is connected to the coolant pipeline of the target energy storage device.

[0022] When the outlet temperature Two is within the second set temperature range, it enters the internal circulation operation mode; in the internal circulation operation mode, the compressor is turned off, the second cold water channel is shut off, and the first cold water channel is connected to the coolant pipeline of the target energy storage device.

[0023] When the outlet temperature Two is within the third set temperature range, it enters the low-temperature refrigeration operation mode; in the low-temperature refrigeration operation mode, the compressor starts, the second refrigerant channel is opened, the third refrigerant channel is closed, the first cold water channel is connected to the coolant pipeline of the target energy storage device, and the second cold water channel is connected to the coolant pipeline of other energy storage devices.

[0024] Wherein, any value within the first set temperature range is less than any value within the second set temperature range, and any value within the second set temperature range is less than any value within the third set temperature range.

[0025] In some embodiments of this application, the controller is further configured as follows:

[0026] Upon receiving the power-on command, when the outdoor ambient temperature Tao is greater than the preset ambient temperature Ts, the system enters the normal mode; in the normal mode, the system monitors the outlet temperature Two of the coolant pipeline of the target energy storage device.

[0027] When the outlet temperature Two is within the third set temperature range, it enters the normal refrigeration operation mode; in the normal refrigeration operation mode, the compressor starts, the second refrigerant channel is shut off, the third refrigerant channel is opened, the second cold water channel is shut off, and the first cold water channel is connected to the coolant pipeline of the target energy storage device;

[0028] When the outlet temperature Two is not within the third set temperature range, it enters the internal circulation operation mode; in the internal circulation operation mode, the compressor is turned off, the second cold water channel is shut off, and the first cold water channel is connected to the coolant pipeline of the target energy storage device.

[0029] In some embodiments of this application, the controller is further configured as follows:

[0030] In low temperature mode, monitor the outdoor ambient temperature; if the monitored outdoor ambient temperature is greater than the preset ambient temperature Ts + compensation temperature ∆T, switch to normal mode.

[0031] In some embodiments of this application, the controller is further configured as follows:

[0032] In normal mode, the outdoor ambient temperature is monitored; if the monitored outdoor ambient temperature is ≤ preset ambient temperature Ts - compensation temperature ∆T, the mode is switched to low temperature mode.

[0033] In some embodiments of this application, the controller is further configured as follows:

[0034] In low-temperature cooling operation mode, the second cold water channel is connected to the coolant pipelines of other energy storage devices in sequence according to the priority of other energy storage devices.

[0035] In some embodiments of this application, the controller is further configured as follows:

[0036] In the low-temperature cooling operation mode, other energy storage devices are sorted according to priority;

[0037] The second cold water channel first connects to the coolant pipeline of the higher priority energy storage device. When the return temperature of the currently connected coolant pipeline reaches the set return temperature, it then connects to the coolant pipeline of the next energy storage device.

[0038] In some embodiments of this application, the controller is further configured as follows:

[0039] When the compressor is stopped and then restarted

[0040] The compressor frequency is controlled by PID based on the preset initial compressor frequency and the target compressor frequency;

[0041] The opening degree of the throttling device is controlled by PID based on the preset initial valve opening degree and target valve opening degree.

[0042] In some embodiments of this application, the controller is further configured as follows:

[0043] A pre-established correspondence between operating mode, outdoor ambient temperature, liquid outlet temperature and initial compressor frequency is used; based on this correspondence, the corresponding initial compressor frequency is obtained according to the current operating mode, outdoor ambient temperature and liquid outlet temperature of the target energy storage device.

[0044] Establish a pre-defined relationship between operating mode, outdoor ambient temperature, liquid outlet temperature and initial valve opening; based on this relationship, obtain the corresponding initial valve opening according to the current operating mode, outdoor ambient temperature and liquid outlet temperature of the target energy storage device.

[0045] Energy storage systems, including:

[0046] The air conditioner mentioned above;

[0047] Multiple energy storage devices;

[0048] An energy storage controller that sends control commands to the air conditioner. Beneficial effects

[0049] Compared with the prior art, the advantages and positive effects of the present invention are as follows: The air conditioning and energy storage system of the present invention is designed with a first heat exchanger having a first refrigerant channel and a first cold water channel; a second heat exchanger having a second refrigerant channel and a second cold water channel; and a third heat exchanger having a third refrigerant channel; the third refrigerant channel is connected in parallel with the second refrigerant channel; after receiving the start-up command, the controller controls the air conditioning operation mode, the on / off state of the second and third refrigerant channels, and the connection or non-connection of the first and second cold water channels with the coolant pipelines of any energy storage device, based on the outdoor ambient temperature and the outlet liquid temperature of the target energy storage device. In the low-temperature cooling operation mode, the compressor starts, the second refrigerant channel is opened, and the third refrigerant channel is closed; the first cold water channel is connected to the coolant pipeline of the target energy storage device to cool the target energy storage device; and the second cold water channel is connected to the coolant pipelines of other energy storage devices to heat the other energy storage devices. Therefore, the air conditioner of this invention can cool the target energy storage device while simultaneously heating other energy storage devices, thus meeting both cooling and heating needs of the energy storage devices and solving the technical problem of not being able to simultaneously cool and heat energy storage devices in the prior art. Furthermore, heat is recovered and utilized through a second heat exchanger to heat other energy storage devices, improving energy utilization efficiency. Attached Figure Description

[0050] Figure 1 is a schematic diagram of the structure of an embodiment of the air conditioner proposed in this invention;

[0051] Figure 2 is a flowchart of an embodiment of the steps performed by the controller of the air conditioner proposed in this invention;

[0052] Figure 3 is a flowchart of another embodiment of the steps performed by the controller of the air conditioner proposed in this invention;

[0053] Figure 4 is a flowchart of another embodiment of the steps performed by the controller of the air conditioner proposed in this invention. Embodiments of the present invention

[0054] Example 1: The air conditioner in this example includes a compressor, a four-way valve, a throttling device (such as an electronic expansion valve Val), a first heat exchanger, a second heat exchanger, a third heat exchanger, a controller, etc., as shown in Figure 1.

[0055] The first heat exchanger has a first refrigerant passage and a first cold water passage. The liquid in the first refrigerant passage exchanges heat with the liquid in the first cold water passage. The first cold water passage is connected to the coolant pipelines of multiple energy storage devices.

[0056] The second heat exchanger has a second refrigerant passage and a second cold water passage. The liquid in the second refrigerant passage exchanges heat with the liquid in the second cold water passage. The second cold water passage is connected to the coolant pipelines of multiple energy storage devices.

[0057] The third heat exchanger has a third refrigerant passage. The third refrigerant passage is connected in parallel with the second refrigerant passage. The compressor, four-way valve, first refrigerant passage, throttling device, and second / third refrigerant passage form a refrigerant circulation loop.

[0058] The second and third refrigerant channels are not connected at the same time.

[0059] When the second refrigerant passage is open, the compressor, four-way valve, first refrigerant passage, throttling device, and second refrigerant passage form a refrigerant circulation loop.

[0060] When the third refrigerant passage is open, the compressor, four-way valve, first refrigerant passage, throttling device, and third refrigerant passage form a refrigerant circulation loop. When the third refrigerant passage is open, the fan located on one side of the third heat exchanger starts, accelerating the heat exchange between the third heat exchanger and the surrounding environment.

[0061] The controller is configured to, upon receiving a start-up command, control the air conditioner's operating mode, the on / off state of the second refrigerant channel and the third refrigerant channel, as well as the connection between the first chilled water channel and the coolant channel of any energy storage device, and the connection between the second chilled water channel and the coolant channel of any energy storage device, based on the outdoor ambient temperature and the outlet temperature of the coolant pipeline of the target energy storage device.

[0062] The air conditioner also includes a first control valve group and a second control valve group.

[0063] The first control valve assembly controls the on / off state of the second and third refrigerant passages. The controller controls the operation of the first control valve assembly, thereby controlling the on / off state of the second and third refrigerant passages.

[0064] The second control valve assembly controls the connection between the first cold water passage and the coolant pipeline of each energy storage device, as well as the connection between the second cold water passage and the coolant pipeline of each energy storage device. The controller controls the operation of the second control valve assembly, thereby controlling the connection between the first cold water passage, the second cold water passage, and the coolant pipeline of each energy storage device.

[0065] Energy storage devices consist of energy storage units and coolant piping. The energy storage units store electrical energy and are used for charging or discharging. The coolant piping is used to heat or cool the energy storage units. The coolant piping has an outlet and an inlet. The outlet temperature is the temperature at the outlet.

[0066] In this embodiment, the energy storage device is an electrical cabinet or a battery pack. Multiple energy storage devices are connected in parallel.

[0067] Air conditioners are used to meet the cooling and heating needs of multiple electrical cabinets or multiple battery packs connected in parallel.

[0068] The coolant pipelines of multiple energy storage devices are connected in parallel. The coolant pipeline of each energy storage device is connected to a first cold water channel and a second cold water channel, respectively. By designing a second control valve group, it is possible to control whether the coolant pipeline of each energy storage device is connected to the first cold water channel, the second cold water channel, or neither of the first and second cold water channels.

[0069] When the air conditioner is cooling, the first heat exchanger acts as an evaporator, and the second or third heat exchanger acts as a condenser. The flow of refrigerant through the second or third heat exchanger is controlled by a first control valve assembly. When the air conditioner is heating, the first heat exchanger acts as a condenser, and the second or third heat exchanger acts as an evaporator.

[0070] After receiving the power-on command, the controller identifies the device number of the target energy storage device contained in the command and monitors the outlet temperature of the coolant pipeline of the target energy storage device. The target energy storage device is the energy storage device that needs to be charged and discharged.

[0071] When the outdoor ambient temperature is low, the energy storage equipment needs to be preheated in order to operate normally.

[0072] When the outdoor ambient temperature Tao ≤ the preset ambient temperature Ts, if the outlet temperature Two of the coolant pipeline of the target energy storage device ≤ the preset low value T1, it indicates that the target energy storage device has a heating (heating or preheating) requirement. The controller then controls the air conditioner to enter the low-temperature heating operation mode; the compressor starts, the second refrigerant channel is shut off, the third refrigerant channel is opened, the second chilled water channel is shut off, and the first chilled water channel is connected to the coolant pipeline of the target energy storage device. That is, the coolant pipeline of the target energy storage device is connected to the first chilled water channel, but not to the second chilled water channel. Specifically, the outlet of the first chilled water channel is connected to the inlet of the target energy storage device, and the return outlet of the first chilled water channel is connected to the outlet of the target energy storage device.

[0073] Therefore, in low-temperature heating mode, the compressor, four-way valve, first refrigerant passage, throttling device, and third refrigerant passage form a refrigerant circulation loop. The refrigerant in the first refrigerant passage exchanges heat with the water in the first cold water passage to increase the water temperature in the first cold water passage. The first cold water passage is connected to the coolant pipeline of the target energy storage device, forming a water circulation loop to heat (or preheat) the energy storage unit of the target energy storage device.

[0074] When the outdoor ambient temperature Tao ≤ preset ambient temperature Ts, if the outlet temperature of the coolant pipeline of the target energy storage device ≥ preset high value T2, it indicates that the target energy storage device has a cooling (temperature reduction) requirement. The controller then controls the air conditioner to enter low-temperature cooling operation mode; the compressor starts, the second refrigerant channel is opened, the third refrigerant channel is closed, the first cold water channel is connected to the coolant pipeline of the target energy storage device, and the second cold water channel is connected to the coolant pipelines of other energy storage devices. That is, the outlet of the first cold water channel is connected to the inlet of the target energy storage device, and the return outlet of the first cold water channel is connected to the outlet of the target energy storage device. The outlet of the second cold water channel is connected to the inlet of other energy storage devices, and the return outlet of the second cold water channel is connected to the outlet of other energy storage devices.

[0075] Therefore, in the low-temperature refrigeration operation mode, the compressor, four-way valve, second refrigerant passage, throttling device, and first refrigerant passage form a refrigerant circulation loop.

[0076] The refrigerant in the first refrigerant channel exchanges heat with the water in the first cold water channel to lower the water temperature in the first cold water channel. The first cold water channel is connected to the coolant pipeline of the target energy storage device, forming a water circulation loop to cool the energy storage units of the target energy storage device.

[0077] The refrigerant in the second refrigerant channel exchanges heat with the water in the second cold water channel to increase the water temperature in the second cold water channel. The second cold water channel is connected to the coolant pipelines of other energy storage devices to form a water circulation loop, which heats (or preheats) the energy storage units of other energy storage devices.

[0078] Therefore, in the low-temperature cooling operation mode, the cooling (cooling) requirements of the target energy storage device are met, as well as the heating (preheating or heating) requirements of other energy storage devices.

[0079] In this embodiment, the air conditioner is designed with a first heat exchanger having a first refrigerant channel and a first chilled water channel; a second heat exchanger having a second refrigerant channel and a second chilled water channel; and a third heat exchanger having a third refrigerant channel. The third refrigerant channel is connected in parallel with the second refrigerant channel. After receiving a start-up command, the controller controls the air conditioner's operating mode, the on / off state of the second and third refrigerant channels, and the connection status of the first and second chilled water channels with the coolant lines of any energy storage device, based on the outdoor ambient temperature and the outlet liquid temperature of the target energy storage device. In the low-temperature cooling operation mode, the compressor starts, the second refrigerant channel is opened, and the third refrigerant channel is closed; the first chilled water channel is connected to the coolant line of the target energy storage device to cool it; and the second chilled water channel is connected to the coolant lines of other energy storage devices to heat them. Therefore, the air conditioner in this embodiment can cool the target energy storage device while heating other energy storage devices, simultaneously meeting the cooling and heating needs of the energy storage devices and solving the technical problem in the prior art that it cannot simultaneously cool and heat energy storage devices. Furthermore, heat is recovered and utilized through the second heat exchanger to heat other energy storage devices, improving energy utilization efficiency.

[0080] The outlet of the first cold water channel is connected to the inlet of multiple energy storage devices via a first outlet pipe; the return outlet of the first cold water channel is connected to the outlet of multiple energy storage devices via a first return pipe. The first outlet pipe includes a first main outlet pipe L1 and multiple first outlet branch pipes. The first return pipe includes a first main return pipe L2 and multiple first return branch pipes.

[0081] The outlet of the second cold water channel is connected to the inlet of multiple energy storage devices via a second outlet pipe; the return outlet of the second cold water channel is connected to the outlet of multiple energy storage devices via a second return pipe. The second outlet pipe includes a second main outlet pipe L3 and multiple second branch outlet pipes. The second return pipe includes a second main return pipe L4 and multiple second branch return pipes.

[0082] In some embodiments of this application, a first water pump is provided on the first water outlet pipe. Specifically, the first water pump is installed on the first main water outlet L1 to provide power for the flow of water in the first water outlet pipe.

[0083] In some embodiments of this application, a second water pump is provided on the second water outlet pipe. Specifically, the second water pump is installed on the second main water outlet L3 to provide power for the flow of water in the second water outlet pipe.

[0084] In some embodiments of this application, in order to facilitate the control of whether the first cold water channel, the second cold water channel and the coolant pipeline of each energy storage device are connected, the second control valve group includes a plurality of first three-way valves and a plurality of second three-way valves.

[0085] The outlet of the first cold water channel is connected to the first main outlet L1. The first main outlet L1 is connected to multiple first branch outlet pipes, and the multiple branch outlet pipes are connected to the first ports of multiple first three-way valves in a one-to-one correspondence.

[0086] The outlet of the second cold water channel is connected to the second main outlet L3. The second main outlet L3 is connected to multiple second branch outlet pipes, and the multiple branch outlet pipes are connected to the second ports of multiple first three-way valves one by one.

[0087] The third ports of multiple first three-way valves are connected one-to-one with the liquid inlets of multiple energy storage devices.

[0088] The return water inlet of the first cold water channel is connected to the first return water main L2. The first return water main L2 is connected to multiple first return water branch pipes, and the multiple first return water branch pipes are connected to the first ports of multiple second three-way valves one by one.

[0089] The return water inlet of the second cold water channel is connected to the second return water main L4. The second return water main L4 is connected to multiple second return water branch pipes, and the multiple second return water branch pipes are connected to the second ports of multiple second three-way valves one by one.

[0090] The third ports of multiple second three-way valves are connected one-to-one with the liquid outlets of multiple energy storage devices.

[0091] Therefore, each energy storage device is equipped with a first three-way valve at the liquid inlet and a second three-way valve at the liquid outlet.

[0092] The air conditioning controller controls each first three-way valve and each second three-way valve respectively, so as to control the coolant pipeline of each energy storage device to be connected to the first cold water channel, or connected to the second cold water channel, or not connected to either the first cold water channel or the second cold water channel.

[0093] For example, as shown in Figure 1, an air conditioner can cool or heat four parallel energy storage devices.

[0094] The inlet of the energy storage device 1 is connected to the third port of the first three-way valve V11. The first port of the first three-way valve V11 is connected to the first main outlet L1 through the corresponding first outlet branch pipe. The second port of the first three-way valve V11 is connected to the second main outlet L3 through the corresponding second outlet branch pipe.

[0095] The outlet of the energy storage device 1 is connected to the third port of the second three-way valve V21. The first port of the second three-way valve V21 is connected to the first return water main L2 through the corresponding first return water branch pipe. The second port of the second three-way valve V21 is connected to the second return water main L4 through the corresponding second return water branch pipe.

[0096] The air conditioning controller controls the first three-way valve V11 and the second three-way valve V21, so that the coolant pipeline of the energy storage device 1 is connected to the first cold water channel, or connected to the second cold water channel, or not connected to either of the two cold water channels.

[0097] The inlet of the energy storage device 2 is connected to the third port of the first three-way valve V12. The first port of the first three-way valve V12 is connected to the first main outlet L1 through the corresponding first outlet branch pipe. The second port of the first three-way valve V12 is connected to the second main outlet L3 through the corresponding second outlet branch pipe.

[0098] The outlet of the energy storage device 2 is connected to the third port of the second three-way valve V22. The first port of the second three-way valve V22 is connected to the first return water main L2 through the corresponding first return water branch pipe. The second port of the second three-way valve V22 is connected to the second return water main L4 through the corresponding second return water branch pipe.

[0099] The air conditioning controller controls the first three-way valve V12 and the second three-way valve V22, so that the coolant pipeline of the energy storage device 2 is connected to the first cold water channel, or connected to the second cold water channel, or not connected to either of the two cold water channels.

[0100] The inlet of the energy storage device 3 is connected to the third port of the first three-way valve V13. The first port of the first three-way valve V13 is connected to the first main outlet L1 through the corresponding first outlet branch pipe. The second port of the first three-way valve V13 is connected to the second main outlet L3 through the corresponding second outlet branch pipe.

[0101] The outlet of the energy storage device 3 is connected to the third port of the second three-way valve V23. The first port of the second three-way valve V23 is connected to the first return water main L2 through the corresponding first return water branch pipe. The second port of the second three-way valve V23 is connected to the second return water main L4 through the corresponding second return water branch pipe.

[0102] The air conditioning controller controls the first three-way valve V13 and the second three-way valve V23, so that the coolant pipeline of the energy storage device 3 is connected to the first cold water channel, or connected to the second cold water channel, or not connected to either of the two cold water channels.

[0103] The inlet of the energy storage device 4 is connected to the third port of the first three-way valve V14. The first port of the first three-way valve V14 is connected to the first main outlet L1 through the corresponding first outlet branch pipe. The second port of the first three-way valve V14 is connected to the second main outlet L3 through the corresponding second outlet branch pipe.

[0104] The outlet of the energy storage device 4 is connected to the third port of the second three-way valve V24. The first port of the second three-way valve V24 is connected to the first return water main L2 through the corresponding first return water branch pipe. The second port of the second three-way valve V24 is connected to the second return water main L4 through the corresponding second return water branch pipe.

[0105] The air conditioning controller controls the first three-way valve V14 and the second three-way valve V24, so that the coolant pipeline of the energy storage device 4 is connected to the first cold water channel, or connected to the second cold water channel, or not connected to either of the two cold water channels.

[0106] In some embodiments of this application, in order to facilitate the control of the opening and closing of the second refrigerant passage and the third refrigerant passage, the first control valve assembly includes a first shut-off valve assembly and a second shut-off valve assembly.

[0107] The first shut-off valve assembly is used to control the opening and closing of the second refrigerant passage.

[0108] The second shut-off valve assembly is used to control the opening and closing of the third refrigerant passage.

[0109] The air conditioning controller controls the operation of the first shut-off valve assembly, thereby controlling the opening and closing of the second refrigerant passage.

[0110] The air conditioning controller controls the operation of the second shut-off valve assembly, thereby controlling the opening and closing of the third refrigerant passage.

[0111] In some embodiments of this application, to facilitate the control of the opening and closing of the second refrigerant passage, the first shut-off valve assembly includes two shut-off valves: shut-off valve V31 and shut-off valve V32. One shut-off valve V31 is located at the first inlet and outlet of the second refrigerant passage; the other shut-off valve V32 is located at the second inlet and outlet of the second refrigerant passage. When both shut-off valves V31 and V32 are open, the second refrigerant passage is open.

[0112] In some embodiments of this application, to facilitate the control of the opening and closing of the third refrigerant passage, the second shut-off valve assembly includes two shut-off valves: shut-off valve V33 and shut-off valve V34. One shut-off valve V33 is located at the first inlet and outlet of the third refrigerant passage; the other shut-off valve V34 is located at the second inlet and outlet of the third refrigerant passage. When both shut-off valves V33 and V34 are open, the third refrigerant passage is open.

[0113] In some embodiments of this application, the first heat exchanger is a plate heat exchanger, which has high heat exchange efficiency and low heat loss.

[0114] In some embodiments of this application, the second heat exchanger is a plate heat exchanger, which has high heat exchange efficiency and low heat loss.

[0115] In some embodiments of this application, a first expansion tank is provided on the first water outlet pipe. The first expansion tank is specifically installed on the first main water outlet L1. The first expansion tank is used to accommodate water expansion, avoid water pressure fluctuations, and also serves to replenish water, ensuring the safety and reliability of the air conditioner operation.

[0116] In some embodiments of this application, a second expansion tank is provided on the second water outlet pipe. Specifically, the second expansion tank is installed on the second main water outlet pipe L3. The second expansion tank is used to accommodate water expansion, preventing water pressure fluctuations, and also serves to replenish water, ensuring the safety and reliability of the air conditioner operation.

[0117] In some embodiments of this application, temperature sensors are respectively installed at the outlet and return outlet of the first cold water channel to facilitate the collection of the temperature at the outlet and return outlet of the first cold water channel. The temperature sensors send the collected temperature signals to the air conditioning controller.

[0118] In some embodiments of this application, temperature sensors are respectively installed at the outlet and return outlet of the second cold water channel to facilitate the collection of the temperature at the outlet and return outlet of the second cold water channel. The temperature sensors send the collected temperature signals to the air conditioning controller.

[0119] In some embodiments of this application, temperature sensors are respectively installed at the inlet and outlet of the coolant pipeline of the energy storage device to facilitate the collection of the temperature at the inlet and outlet of the energy storage device. The temperature sensors send the collected temperature signals to the air conditioning controller.

[0120] Air conditioner operating modes include: low temperature heating mode, low temperature cooling mode, normal cooling mode, and internal circulation mode.

[0121] When the outdoor ambient temperature Tao is less than or equal to the preset ambient temperature Ts, the system enters low-temperature mode. In low-temperature mode, the air conditioner enters one of the following operating modes based on the outlet liquid temperature Two of the coolant pipeline of the target energy storage device: low-temperature heating mode, low-temperature cooling mode, or internal circulation mode.

[0122] When the outdoor ambient temperature Tao is greater than the preset ambient temperature Ts, the system enters normal mode. In normal mode, the air conditioner enters either normal cooling operation mode or internal circulation operation mode based on the outlet liquid temperature Two of the coolant pipeline of the target energy storage device.

[0123] In some embodiments of this application, the controller is also configured to perform the following steps, as shown in FIG2.

[0124] Step S11: After receiving the power-on command, obtain the outdoor ambient temperature Tao.

[0125] Step S12: When the outdoor ambient temperature Tao ≤ the preset ambient temperature Ts, enter the low temperature mode.

[0126] Step S13: In low temperature mode, monitor the outlet temperature Two of the coolant pipeline of the target energy storage device.

[0127] Step S14-1: When the outlet liquid temperature Two of the target energy storage device is within the first set temperature range, it enters the low-temperature heating operation mode; in the low-temperature heating operation mode, the compressor starts, the second refrigerant channel is shut off, the third refrigerant channel is opened, the second cold water channel is shut off, and the first cold water channel is connected to the coolant pipeline of the target energy storage device. The fan starts.

[0128] When the outlet liquid temperature Two of the target energy storage device is within the first set temperature range, it indicates that the outlet liquid temperature Two is too low, the energy storage unit of the target energy storage device cannot work normally, and the target energy storage device needs to be heated. Therefore, the air conditioner is controlled to enter the low temperature heating operation mode.

[0129] In low-temperature heating operation mode, the compressor, four-way valve, first refrigerant passage, throttling device, and third refrigerant passage form a refrigerant circulation loop. The refrigerant in the first refrigerant passage exchanges heat with the water in the first cold water passage to raise the water temperature. The first cold water passage is connected to the coolant pipeline of the target energy storage device, forming a water circulation loop to heat (or preheat) the energy storage unit of the target energy storage device, enabling the energy storage unit to reach a normal operating temperature as quickly as possible.

[0130] Step S14-2: When the outlet liquid temperature Two of the target energy storage device is within the second set temperature range, it enters the internal circulation operation mode; in the internal circulation operation mode, the compressor is turned off, the second cold water channel is shut off, and the first cold water channel is connected to the coolant pipeline of the target energy storage device.

[0131] When the outlet liquid temperature Two of the target energy storage device is within the second set temperature range, it indicates that the outlet liquid temperature Two is suitable. Therefore, the compressor is turned off and the refrigerant is not circulated to save energy. The first cold water channel is connected to the coolant pipeline of the target energy storage device to keep the water circulation loop unobstructed and to heat the energy storage unit of the target energy storage device.

[0132] Step S14-3: When the outlet liquid temperature Two of the target energy storage device is within the third set temperature range, it enters the low-temperature cooling operation mode; in the low-temperature cooling operation mode, the compressor starts, the second refrigerant channel is opened, the third refrigerant channel is closed, the first cold water channel is connected to the coolant pipeline of the target energy storage device, and the second cold water channel is connected to the coolant pipeline of other energy storage devices.

[0133] When the outlet liquid temperature Two of the target energy storage device is within the third set temperature range, it indicates that the outlet liquid temperature Two is too high and the target energy storage device needs to be cooled down. Therefore, the air conditioner is controlled to enter the low-temperature cooling operation mode.

[0134] In low-temperature refrigeration operation mode, the compressor, four-way valve, second refrigerant passage, throttling device, and first refrigerant passage form a refrigerant circulation loop.

[0135] The refrigerant in the first refrigerant channel exchanges heat with the water in the first cold water channel to lower the water temperature in the first cold water channel. The first cold water channel is connected to the coolant pipeline of the target energy storage device to form a water circulation loop, which cools the energy storage unit of the target energy storage device and prevents the energy storage unit from burning out due to high temperature.

[0136] The refrigerant in the second refrigerant channel exchanges heat with the water in the second cold water channel to raise the water temperature in the second cold water channel. The second cold water channel is connected to the coolant pipelines of other energy storage devices, forming a water circulation loop to heat (or preheat) the energy storage units of other energy storage devices, allowing them to prepare for normal operation in advance. Moreover, heat is recovered and utilized through the second heat exchanger, improving energy utilization efficiency.

[0137] Any value within the first set temperature range is less than any value within the second set temperature range.

[0138] Any value within the second set temperature range is less than any value within the third set temperature range.

[0139] For example, the first set temperature range is: (-∞, preset low value T1];

[0140] The second set temperature range is: (preset low value T1, preset high value T2);

[0141] The third set temperature range is: [Preset high value T2, +∞).

[0142] By designing steps S11 to S14, when the outdoor ambient temperature Tao ≤ the preset ambient temperature Ts, the air conditioner is controlled to enter either a low-temperature heating mode, an internal circulation mode, or a low-temperature cooling mode based on the outlet liquid temperature Two of the target energy storage device, ensuring the normal operation of the target energy storage device. Furthermore, while cooling the target energy storage device, it can also heat other energy storage devices, allowing them to prepare for normal operation in advance, thus achieving heat recovery and utilization and improving energy efficiency.

[0143] In some embodiments of this application, the controller is also configured to perform the following steps, as shown in FIG3.

[0144] Step S21: After receiving the power-on command, obtain the outdoor ambient temperature Tao.

[0145] Step S22: When the outdoor ambient temperature Tao is greater than the preset ambient temperature Ts, enter the normal mode.

[0146] Step S23: In normal mode, monitor the outlet temperature Two of the coolant pipeline of the target energy storage device.

[0147] Step S24-1: When the outlet liquid temperature Two of the target energy storage device is within the third set temperature range, the device enters the normal cooling operation mode. In the normal cooling operation mode, the compressor starts, the second refrigerant channel is shut off, the third refrigerant channel is opened, the second cold water channel is shut off, and the first cold water channel is connected to the coolant pipeline of the target energy storage device. The fan starts.

[0148] When the outlet liquid temperature Two of the target energy storage device is within the third set temperature range, it indicates that the outlet liquid temperature Two is too high and the target energy storage device needs to be cooled down. Therefore, the air conditioner is controlled to enter the normal cooling operation mode.

[0149] In normal refrigeration operation mode, the compressor, four-way valve, third refrigerant passage, throttling device, and first refrigerant passage form a refrigerant circulation loop. The refrigerant in the first refrigerant passage exchanges heat with the water in the first cold water passage to lower the water temperature in the first cold water passage. The first cold water passage is connected to the coolant pipeline of the target energy storage device, forming a water circulation loop to cool the energy storage unit of the target energy storage device and prevent the energy storage unit from burning out due to high temperature.

[0150] Step S24-2: When the outlet temperature Two of the target energy storage device is not within the third set temperature range, the internal circulation operation mode is entered; in the internal circulation operation mode, the compressor is turned off, the second cold water channel is shut off, and the first cold water channel is connected to the coolant pipeline of the target energy storage device.

[0151] When the outlet temperature Two of the target energy storage device is not within the third set temperature range, it indicates that the outlet temperature Two is suitable. Therefore, the compressor is turned off and the refrigerant is not circulated to save energy. The first cold water channel is connected to the coolant pipeline of the target energy storage device to keep the water circulation loop unobstructed and to heat the energy storage unit of the target energy storage device.

[0152] By designing steps S21 to S24, when the outdoor ambient temperature Tao is greater than the preset ambient temperature Ts, the air conditioner is controlled to enter the internal circulation operation mode or the normal cooling operation mode according to the liquid outlet temperature Two of the target energy storage device, thus ensuring the normal operation of the target energy storage device.

[0153] In some embodiments of this application, in order to achieve precise control of the air conditioner, the controller is further configured as follows:

[0154] In low temperature mode, monitor the outdoor ambient temperature; if the monitored outdoor ambient temperature is greater than the preset ambient temperature Ts + compensation temperature ∆T, switch to normal mode.

[0155] In some embodiments of this application, in order to achieve precise control of the air conditioner, the controller is further configured as follows:

[0156] In normal mode, the outdoor ambient temperature is monitored; if the monitored outdoor ambient temperature is ≤ preset ambient temperature Ts - compensation temperature ∆T, the mode is switched to low temperature mode.

[0157] The design of the compensation temperature ∆T can avoid frequent switching between low temperature mode and normal mode.

[0158] In some embodiments of this application, the controller is further configured as follows:

[0159] In the low-temperature cooling operation mode, according to the priority of other energy storage devices, the second cold water channel is controlled to connect to the coolant pipelines of other energy storage devices in sequence, so as to preheat the other energy storage devices in sequence.

[0160] According to priority, the second cold water channel was used to preheat other energy storage devices in sequence, ensuring the preheating effect of other energy storage devices.

[0161] In some embodiments of this application, the controller is further configured as follows:

[0162] In the low-temperature cooling operation mode, other energy storage devices are sorted according to priority;

[0163] The second cold water channel first connects to the coolant pipeline of the higher priority energy storage device. When the return temperature of the currently connected coolant pipeline reaches the set return temperature, the coolant pipeline of the next energy storage device is then connected to ensure the preheating effect of the connected energy storage devices.

[0164] When the return temperature of the currently connected coolant pipeline is greater than or equal to the set return temperature, it indicates that the preheating requirements of the already connected energy storage device have been met, and then the coolant pipeline of the next energy storage device can be connected.

[0165] If the preheating requirements of high-priority energy storage devices cannot be met, the next energy storage device will not be preheated.

[0166] In some embodiments of this application, in order to achieve precise control of the compressor and throttling device and ensure the normal operation of the air conditioner, the controller is further configured as follows:

[0167] When the compressor is stopped and then restarted, the compressor frequency is controlled by PID based on the preset initial compressor frequency and target compressor frequency; the opening degree of the throttling device is controlled by PID based on the preset initial valve opening degree and target valve opening degree.

[0168] In some embodiments of this application, to facilitate obtaining the initial compressor frequency and initial valve opening, the controller is further configured as follows:

[0169] Establish a pre-defined relationship between operating mode, outdoor ambient temperature, liquid outlet temperature and initial compressor frequency; based on this relationship, obtain the corresponding initial compressor frequency according to the current operating mode, outdoor ambient temperature and liquid outlet temperature of the target energy storage device.

[0170] Establish a pre-defined relationship between operating mode, outdoor ambient temperature, liquid outlet temperature and initial valve opening; based on this relationship, obtain the corresponding initial valve opening according to the current operating mode, outdoor ambient temperature and liquid outlet temperature of the target energy storage device.

[0171] A table is pre-established to correspond to the operating mode, outdoor ambient temperature, liquid outlet temperature, and initial compressor frequency. By looking up the table, the corresponding initial compressor frequency can be obtained easily, conveniently, and accurately.

[0172] A table is pre-established to correspond to the operating mode, outdoor ambient temperature, liquid outlet temperature, and initial valve opening. By looking up the table, the corresponding initial valve opening can be obtained easily, conveniently, and accurately.

[0173] The working process of an air conditioner will be explained in detail below.

[0174] In winter, the energy storage device (energy storage unit is a battery) is too cold to charge and discharge directly. It needs to be heated first to raise the battery temperature before charging and discharging can begin. During this time, the air conditioner needs to operate in low-temperature heating mode. In low-temperature heating mode, the refrigerant circulation path is: compressor → first heat exchanger → electronic expansion valve → third heat exchanger → compressor. The first heat exchanger heats the energy storage device. At this time, the valve group of the second heat exchanger (stop valves V31 and V32) is closed, and the valve group of the third heat exchanger (stop valves V33 and V34) is open.

[0175] For example, if only energy storage device 1 needs to be put into operation, then control three-way valves V11 and V21 are opened, connecting the coolant pipeline of energy storage device 1 to the first cold water channel of the first heat exchanger, but not to the second cold water channel of the second heat exchanger. The first heat exchanger then heats energy storage device 1. All other shut-off valves are closed, and the device is in a shutdown state.

[0176] When the energy storage device's temperature rises, it generates heat during charging and discharging. At this time, the air conditioner needs to operate in low-temperature cooling mode. In low-temperature cooling mode, the refrigerant circulation path is: compressor → second heat exchanger → electronic expansion valve → first heat exchanger → compressor. During this time, the valve group (stop valves V31 and V32) of the second heat exchanger is open, and the valve group (stop valves V33 and V34) of the third heat exchanger is closed. The second heat exchanger acts as a condenser, and the heat it generates preheats the remaining energy storage devices. The corresponding three-way valve of the energy storage device requiring preheating opens, connecting to the second cold water channel of the second heat exchanger, allowing the second heat exchanger to preheat the energy storage device. When the energy storage device is needed (during charging and discharging), it can be directly put into use. After being put into use, the energy storage device generates heat during charging and discharging, and the three-way valve of this energy storage device switches to connect to the first cold water channel of the first heat exchanger, allowing the first heat exchanger to cool the energy storage device.

[0177] For example, if all three-way valves V12, V22, V13, V23, V14, and V24 are connected to the second cold water channel of the second heat exchanger, then energy storage devices 2, 3, and 4 are in a preheating state. When energy storage device 2 is put into use, its initial temperature is low, and heating will continue for a period of time. When the heat generated by charging and discharging becomes large, three-way valves V12 and V22 will switch to connect to the first cold water channel of the first heat exchanger, and the first heat exchanger will begin to cool energy storage device 2. Energy storage devices 3 and 4 will still be in a preheating state. If any energy storage device is taken out of use at this time, its corresponding three-way valve will also switch from connecting to the first cold water channel to connecting to the second cold water channel, entering the preheating state.

[0178] This allows for switching between heating and cooling needs of any energy storage device, enabling different energy storage devices to operate simultaneously in both modes. For example, energy storage devices 1 and 2 can cool, while devices 3 and 4 can heat, preventing all devices from operating only one mode at a time. The heat from the second heat exchanger is fully recovered and utilized, preventing waste. The battery management system of the energy storage devices also offers greater flexibility, allowing for the selection of which device operates based on actual conditions. Simultaneous operation is not required; instead, the system can determine in real-time whether heating or cooling is needed based on the temperature of each battery and open the corresponding three-way valve.

[0179] The air conditioner of this application recovers and utilizes heat through a second heat exchanger for heating and preheating of other energy storage devices, improving energy utilization efficiency and avoiding the waste of heat dissipated by the condenser in traditional heat pump cycles. In traditional heat pump air conditioners, the heat dissipated by the condenser equals the heat absorbed by the evaporator plus the compressor power during cooling, resulting in complete waste of this heat. However, in this application, the heat dissipated by the condenser is converted into heating capacity. This application is equivalent to two traditional heat pumps, one for cooling and the other for heating.

[0180] When the energy storage device is not started, the condenser is used to preheat the energy storage device; when the energy storage device is running, usually when it is just started up and the battery heats up little and the temperature is still low, the condenser is used to heat the energy storage device; in both cases, the condenser is actually used to heat the energy storage device.

[0181] The air conditioner in this embodiment can achieve the following: (1) One air conditioner can meet the needs of simultaneous heating and cooling. (2) Each energy storage device has three states: cooling, heating, and shutdown. The cooling / heating of each energy storage device can be controlled independently. When the energy storage device is shut down, this flow path can also be in a shutdown state. At the same time, different energy storage devices can be in the three states of heating, cooling, and shutdown respectively, without all energy storage devices needing to cool or heat at the same time. (3) The heat from the second heat exchanger can be reused in the low-temperature cooling mode, improving the energy efficiency.

[0182] The air conditioner in this embodiment helps improve the precision control of the battery thermal management system. It can collect real-time data of each battery through the battery management system, thereby achieving precise control of the battery cabinet.

[0183] The air conditioner in this embodiment recovers and utilizes almost 100% of the condensation heat, which can still be used in the energy storage device. It can also be adjusted according to the specific operating conditions of a single energy storage device, achieving high utilization rate, no need to transfer to other industries, high precision control, and simultaneous cooling and heating by a single air conditioner.

[0184] The control logic of the air conditioner will be explained in detail below with reference to Figure 4.

[0185] Assume the preset ambient temperature Ts is 0℃, the preset low value T1 is 0℃, the preset high value T2 is 15℃, the compensation temperature ∆T is 5℃, and the set return temperature is 0℃.

[0186] (1) After receiving the power-on command, the controller determines whether the outdoor ambient temperature Tao ≤ Ts. Ts = 0℃.

[0187] If yes, then enter low temperature mode. If not, then enter normal mode.

[0188] (2) After entering the low temperature mode, determine whether the liquid outlet temperature Two≤T1 is satisfied. T1=0℃.

[0189] If so, it will enter the low-temperature heating mode.

[0190] If not, continue to determine whether the liquid outlet temperature Two≥T2, where T2=15℃.

[0191] If Two≥T2 is satisfied, the system enters low-temperature refrigeration mode. If not, it enters internal circulation mode.

[0192] (3) After entering the normal mode, determine whether the liquid outlet temperature Two≥T2 is satisfied. T2=15℃.

[0193] If yes, it will enter normal cooling mode. If not, it will enter internal circulation mode.

[0194] (4) When the compressor is restarted after being stopped, that is, when it is started for the first time after receiving the start command, it is necessary to determine the initial compressor frequency Hz0 / initial valve opening K0 / initial fan speed F0 to enter PID control. The Hz0 / K0 / F0 and PID control logic are different under different operating modes / outdoor ambient temperature / outlet liquid temperature.

[0195] After the compressor starts, there is no need to determine the initial values ​​Hz0 / K0 / K0 for each cycle. Instead, the compressor frequency Hz / electronic expansion valve opening K / fan speed F from the previous cycle are substituted into the current cycle for PID calculation.

[0196] The PID control compressor system operates by continuously feeding back Two and Tao values ​​to adjust the mode promptly. Typically, when the outdoor ambient temperature changes beyond the compensation temperature ∆T (e.g., ∆T = 5℃), it will reassess whether to enter low-temperature mode or normal mode before proceeding with the next step of determining the operating mode (cooling / heating / internal circulation). The compensation temperature ∆T prevents frequent large mode jumps. Normally, each startup will only operate in either low-temperature or normal mode because energy storage devices typically discharge when electricity prices are high and charge when prices are low. The start-stop cycles of the energy storage device are relatively short, and the temperature fluctuations are not significant.

[0197] This application primarily targets winter application scenarios. The typical logic under severe winter weather is as follows: Upon startup, the air conditioner immediately enters low-temperature mode. If the time since the last startup is relatively long, the outlet liquid temperature of the energy storage device is close to the ambient temperature (if the interval is short, the outlet liquid temperature is relatively high). When the outlet liquid temperature is low, it enters a low-temperature heating operation mode. The PID control compressor system performs low-temperature heating, simultaneously feeding back values ​​Two and Tao. When the outlet liquid temperature Two rises above 0℃, it enters an internal circulation operation mode. At this time, the target energy storage device, i.e., energy storage device 1, starts (the battery can actually charge and discharge at low current at -15℃, so even at a water temperature above 0℃, the cell temperature will be a few degrees lower, and slow charging is generally not a problem; temperature T1 can also be adjusted to increase the starting charging and discharging temperature). As energy storage device 1 charges and discharges, the outlet liquid temperature Two rises. When Two ≥ 15℃, it switches to a low-temperature cooling operation mode. The target cooling outlet liquid temperature T3 is 20℃. Through PID control, the outlet liquid temperature will be controlled at 20℃. A higher outlet liquid temperature increases the system output, and a lower outlet liquid temperature decreases the system output. In the low-temperature cooling operation mode, the second cold water channel heats the energy storage devices 2 / 3 / 4 to put them in a ready state. According to the charging and discharging requirements, the energy storage devices 2 / 3 / 4 are gradually connected to the grid / disconnected from the grid in sequence. When connected to the grid, the first cold water channel is connected, and when disconnected from the grid, the second cold water channel is connected, and the device enters the ready state.

[0198] Energy storage device preheating and charging / discharging logic:

[0199] (1) When energy storage device 1 is charging, the heat from energy storage device 1 is used to preheat energy storage devices 2 / 3 / 4, with the priority as follows: energy storage device 1 > energy storage device 2 > energy storage device 3 > energy storage device 4. When the return liquid temperature of energy storage device 2 reaches above 0℃, energy storage device 3 is preheated. At the same time, the return liquid temperature of energy storage device 2 is monitored to ensure that it does not fall below 0℃. If it falls below 0℃, the water flow rate of energy storage device 2 needs to be increased. When the return liquid temperature of energy storage device 3 stabilizes, energy storage device 4 is preheated. If a higher priority energy storage device cannot meet the preheating requirements, the next energy storage device will not be preheated.

[0200] (2) When the energy storage device 1 is fully charged, switch the energy storage device 2 to charge. At this time, the three-way valves V11 and V21 are closed, the three-way valves V12 and V22 are connected to the water pump 1 circuit (i.e. the first cold water channel), and the three-way valves V13 and V23 are connected to the water pump 2 circuit (i.e. the second cold water channel). The energy storage device 3 is in the preheating state. After the preheating is completed, the three-way valves V14 and V24 are also connected to the water pump 2 circuit (i.e. the second cold water channel).

[0201] (3) The charging of energy storage devices 3 and 4 is the same as the above steps. (4) The discharging process is the same as the charging process.

[0202] Low-temperature heating operation mode: The compressor starts, and the four-way valve connects port 1 and port 2, and port 3 and port 4; the shut-off valves V33 and V34 open; the fan starts; the water pump 1 starts; the three-way valves V11 and V21 open, connecting the water pump 1 circuit.

[0203] Internal circulation operation mode: compressor system is off; water pump 1 is on; three-way valves V11 and V21 connect the water pump 1 circuit, and energy storage device 1 is connected to the grid.

[0204] Low-temperature refrigeration operation mode: The compressor starts, and ports 1 and 4 of the four-way valve are connected, as are ports 2 and 3; shut-off valves V31 and V32 are open; water pumps 1 and 2 are open; when energy storage device 1 is charging: three-way valves V11 and V21 connect to the water pump 1 circuit, three-way valves V12 and V22 connect to the water pump 2 circuit, and three-way valves V13, V23, V14, and V24 are opened in sequence according to priority after energy storage device 2 has been preheated. After the energy storage device has been preheated, it is still connected in parallel in the water pump 2 circuit for preheating; after energy storage device 1 is fully charged, V11 and V21 are closed, V12 and V22 connect to the water pump 1 circuit, and V13 and V23 are opened. If energy storage device 3 has already been preheated, then V14 and V24 are opened to preheat energy storage device 4.

[0205] Normal refrigeration operation mode: The compressor starts, and ports 1 and 4 of the four-way valve are connected, as are ports 2 and 3; shut-off valves V33 and V34 are open; the fan is on; water pump 1 is on; three-way valves V11, V21, V12, V22, V13, V23, V14, and V24 are connected to the water pump 1 circuit according to the grid connection requirements of the energy storage equipment.

[0206] Example 2: Based on the air conditioner design of Example 1, this Example 2 proposes an energy storage system, including the air conditioner, multiple energy storage devices, and an energy storage controller.

[0207] The energy storage controller controls the charging and discharging of multiple energy storage devices. It communicates with the air conditioner, sending control commands to it.

[0208] For example, the control command is a power-on command, and the energy storage controller sends the power-on command to the air conditioner controller; the power-on command includes the device number of the target energy storage device that needs to be charged and discharged.

[0209] By incorporating the aforementioned air conditioning into the energy storage system, the heating and cooling needs of the energy storage equipment can be met simultaneously, ensuring the smooth charging and discharging of the equipment. Furthermore, heat recovery and utilization are achieved, improving energy efficiency.

[0210] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An air conditioner, characterized in that: include: compressor; Four-way valve; Throttling device; The first heat exchanger has a first refrigerant passage and a first cold water passage; The first cold water channel is connected to the coolant pipelines of multiple energy storage devices; The second heat exchanger has a second refrigerant passage and a second cold water passage; the second cold water passage is connected to the coolant pipelines of multiple energy storage devices respectively. The third heat exchanger has a third refrigerant passage; the third refrigerant passage is connected in parallel with the second refrigerant passage; the compressor, four-way valve, first refrigerant passage, throttling device, and second / third refrigerant passage form a refrigerant circulation loop; The controller is configured to, upon receiving a power-on command, control the air conditioner's operating mode, the on / off state of the second refrigerant channel and the third refrigerant channel, as well as the connection or disconnection between the first cold water channel and the coolant channel of any energy storage device, and the connection or disconnection between the second cold water channel and the coolant channel of any energy storage device, based on the outdoor ambient temperature and the outlet temperature of the coolant pipeline of the target energy storage device.

2. The air conditioner according to claim 1, characterized in that: The controller is further configured to: upon receiving a power-on command, enter a low-temperature mode when the outdoor ambient temperature Tao ≤ a preset ambient temperature Ts; and in the low-temperature mode, monitor the outlet temperature Two of the coolant pipeline of the target energy storage device. When the outlet temperature Two is within the first set temperature range, it enters the low-temperature heating operation mode; in the low-temperature heating operation mode, the compressor starts, the second refrigerant channel is shut off, the third refrigerant channel is opened, the second cold water channel is shut off, and the first cold water channel is connected to the coolant pipeline of the target energy storage device. When the outlet temperature Two is within the second set temperature range, it enters the internal circulation operation mode; in the internal circulation operation mode, the compressor is turned off, the second cold water channel is shut off, and the first cold water channel is connected to the coolant pipeline of the target energy storage device. When the outlet temperature Two is within the third set temperature range, it enters the low-temperature refrigeration operation mode; in the low-temperature refrigeration operation mode, the compressor starts, the second refrigerant channel is opened, the third refrigerant channel is closed, the first cold water channel is connected to the coolant pipeline of the target energy storage device, and the second cold water channel is connected to the coolant pipeline of other energy storage devices. Wherein, any value within the first set temperature range is less than any value within the second set temperature range, and any value within the second set temperature range is less than any value within the third set temperature range.

3. The air conditioner according to claim 1, characterized in that: The controller is further configured to: upon receiving a power-on command, enter a normal mode when the outdoor ambient temperature Tao is greater than the preset ambient temperature Ts; and in the normal mode, monitor the outlet temperature Two of the coolant pipeline of the target energy storage device. When the outlet temperature Two is within the third set temperature range, it enters the normal refrigeration operation mode; in the normal refrigeration operation mode, the compressor starts, the second refrigerant channel is shut off, the third refrigerant channel is opened, the second cold water channel is shut off, and the first cold water channel is connected to the coolant pipeline of the target energy storage device; When the outlet temperature Two is not within the third set temperature range, it enters the internal circulation operation mode; in the internal circulation operation mode, the compressor is turned off, the second cold water channel is shut off, and the first cold water channel is connected to the coolant pipeline of the target energy storage device.

4. The air conditioner according to claim 1, characterized in that: The controller is also configured to: monitor the outdoor ambient temperature in low temperature mode; if the monitored outdoor ambient temperature is greater than the preset ambient temperature Ts + compensation temperature ∆T, then switch to normal mode.

5. The air conditioner according to claim 1, characterized in that: The controller is also configured to: monitor the outdoor ambient temperature in normal mode; if the monitored outdoor ambient temperature is ≤ preset ambient temperature Ts - compensation temperature ∆T, then switch to low temperature mode.

6. The air conditioner according to claim 2, characterized in that: The controller is also configured to, in low-temperature refrigeration operation mode, control the second cold water channel to connect sequentially to the coolant pipelines of other energy storage devices according to the priority of other energy storage devices.

7. The air conditioner according to claim 2, characterized in that: The controller is further configured to: sort other energy storage devices according to priority in low-temperature cooling operation mode; the second cold water channel first connects to the coolant pipeline of the energy storage device with higher priority, and when the return temperature of the currently connected coolant pipeline reaches the set return temperature, then connects to the coolant pipeline of the next energy storage device.

8. The air conditioner according to any one of claims 1 to 7, characterized in that: The controller is also configured to: when the compressor is stopped and restarted, perform PID control on the compressor frequency according to the preset initial compressor frequency and target compressor frequency; and perform PID control on the opening degree of the throttling device according to the preset initial valve opening degree and target valve opening degree.

9. The air conditioner according to claim 8, characterized in that: The controller is also configured to: A pre-established correspondence between operating mode, outdoor ambient temperature, liquid outlet temperature and initial compressor frequency is used; based on this correspondence, the corresponding initial compressor frequency is obtained according to the current operating mode, outdoor ambient temperature and liquid outlet temperature of the target energy storage device. Establish the correspondence between operating mode, outdoor ambient temperature, liquid outlet temperature and initial valve opening in advance; Based on this correspondence, the corresponding initial valve opening is obtained according to the current operating mode, outdoor ambient temperature, and liquid outlet temperature of the target energy storage device.

10. An energy storage system, characterized in that: include: The air conditioner as described in any one of claims 1 to 9; Multiple energy storage devices; An energy storage controller that sends control commands to the air conditioner.

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