Water chiller control method, device, equipment and medium

Abstract

The application discloses a water chilling unit control method, device, equipment and medium, comprising: firstly determining a target outlet water temperature and a target opening number of electromagnetic valves in the water chilling unit based on a current cold load demand of the battery swap station. The target outlet water temperature and the target opening number are state parameters of the water chilling unit in an ideal state. To achieve the above-mentioned state parameters, the electromagnetic valves with the target opening number are directly opened; then a corresponding preset control strategy is determined based on a comparison relationship between the target opening number and a preset low-load threshold, and the working parameters of the water chilling unit are adjusted according to the preset control strategy until the actual outlet water temperature of the water chilling unit is less than or equal to the target outlet water temperature; wherein the working parameters include at least one of the rotating speed of the water pump in the water chilling unit, the frequency of the variable frequency compressor and the opening degree of the electronic expansion valve. In this way, the actual cold load supply of the water chilling unit is just greater than or equal to the cold load demand of the battery swap station.

Description

Technical Field

[0001] This invention relates to the field of thermal management technology for battery swapping stations, and in particular to a control method, device, equipment, and medium for a chiller unit. Background Technology

[0002] By 2025, new energy vehicles will account for approximately 20% of total new car sales. By around 2035, pure electric vehicles will become the mainstream of new vehicle sales, and public sector vehicles will be fully electrified. Correspondingly, to address charging anxiety, the government is strongly supporting the construction of battery swapping stations.

[0003] Existing battery swapping stations often employ variable load solutions during charging and discharging, typically using constant flow and fixed frequency chiller units for cooling. In developing this application, the inventors discovered at least the following problems with the prior art: while this cooling method is relatively simple to control, the chiller units do not provide matching cooling capacity according to changes in the battery swapping station's load, making accurate temperature control impossible and resulting in high overall system energy consumption. Summary of the Invention

[0004] Therefore, it is necessary to provide chiller control methods, devices, equipment and media to improve the problems that chillers cannot provide matching cooling capacity according to changes in the load of the battery swapping station, cannot accurately control the temperature, and have high overall system energy consumption.

[0005] A chiller unit control method, the method comprising:

[0006] The target outlet water temperature of the chiller unit and the target number of solenoid valves to be opened in the chiller unit are determined based on the current cooling load demand of the battery swapping station.

[0007] The target number of solenoid valves to be opened is opened, and the corresponding preset control strategy is determined based on the comparison between the target number of valves to be opened and the preset low load threshold.

[0008] The operating parameters of the chiller unit are adjusted according to the preset control strategy until the actual outlet water temperature of the chiller unit is less than or equal to the target outlet water temperature; wherein the operating parameters include at least one of the following: the speed of the water pump in the chiller unit, the frequency of the variable frequency compressor, and the opening degree of the electronic expansion valve.

[0009] In one embodiment, adjusting the operating parameters of the chiller unit according to the preset control strategy includes:

[0010] Based on the correspondence between the number of solenoid valves opened and the flow rate, the target water flow rate of the chiller unit is determined according to the target number of valves opened.

[0011] The pump speed is controlled to adjust the flow rate to match the target water flow rate.

[0012] In one embodiment, adjusting the operating parameters of the chiller unit according to the preset control strategy includes:

[0013] Under the premise of executing the first control strategy, the target intake superheat is determined according to the sum of the current intake superheat of the chiller unit and the preset value; wherein, the first control strategy is the preset control strategy corresponding to when the target number of activations is less than or equal to the preset low load threshold.

[0014] Adjust the opening of the electronic expansion valve according to the target intake superheat.

[0015] In one embodiment, after adjusting the opening of the electronic expansion valve according to the target intake superheat, the method further includes:

[0016] The compressor of the chiller unit is controlled to operate at a preset minimum frequency.

[0017] In one embodiment, adjusting the operating parameters of the chiller unit according to the preset control strategy includes:

[0018] Under the premise of implementing the second control strategy, the opening degree of the electronic expansion valve is adjusted according to the current suction superheat of the chiller unit; wherein, the second control strategy is the preset control strategy corresponding to when the target number of openings is greater than the preset low load threshold.

[0019] In one embodiment, after adjusting the opening of the electronic expansion valve according to the current suction superheat of the chiller unit, the method further includes:

[0020] The target cooling load of the chiller unit is determined based on the target outlet water temperature and the actual outlet water temperature.

[0021] Determine the target speed of the variable frequency compressor based on the target cooling load;

[0022] Adjust the compression frequency of the variable frequency compressor according to the target rotational speed until the actual outlet water temperature of the chiller unit is less than or equal to the target outlet water temperature.

[0023] In one embodiment, determining the target outlet water temperature of the chiller unit and the target number of solenoid valves to be opened within the chiller unit based on the cooling load demand includes:

[0024] Let the number of temporary openings of the solenoid valves in the chiller unit be i = 1, and calculate the temporary flow rate of the chiller unit based on the current number of temporary openings.

[0025] Calculate the provisional outlet water temperature of the chiller unit based on the cooling load demand and the provisional flow rate, and determine whether the provisional outlet water temperature is within the range of the outlet water temperature that the chiller unit can provide.

[0026] If the provisional outlet water temperature is not within the range of the outlet water temperature that the chiller unit can provide, then let i = i + 1, and return to the step of calculating the provisional flow rate of the chiller unit based on the current provisional number of openings and subsequent steps.

[0027] If the provisional outlet water temperature is within the range of the outlet water temperature that the chiller unit can provide, then the currently determined provisional opening quantity is taken as the target opening quantity, and the currently determined provisional outlet water temperature is taken as the target outlet water temperature.

[0028] A chiller unit control device, the device comprising:

[0029] The parameter acquisition and setting module is used to determine the target outlet water temperature of the chiller unit and the target number of solenoid valves to be opened in the chiller unit based on the current cooling load demand of the battery swapping station.

[0030] The control module is used to open a target number of solenoid valves and determine a corresponding preset control strategy based on a comparison between the target number of valves and a preset low-load threshold; adjust the operating parameters of the chiller unit according to the preset control strategy until the actual outlet water temperature of the chiller unit is less than or equal to the target outlet water temperature; wherein, the operating parameters include at least one of the following: the speed of the water pump in the chiller unit, the frequency of the variable frequency compressor, and the opening degree of the electronic expansion valve.

[0031] A computer-readable storage medium storing a computer program, which, when executed by a processor, causes the processor to perform the steps of the above-described chiller unit control method.

[0032] A chiller unit control device includes a memory and a processor. The memory stores a computer program, which, when executed by the processor, causes the processor to perform the steps of the chiller unit control method described above.

[0033] This invention provides a chiller unit control method, apparatus, equipment, and medium. First, based on the current cooling load demand of the battery swapping station, the target outlet water temperature and the target number of solenoid valves to be opened within the chiller unit are determined. These target outlet water temperature and target number of valves being opened represent the chiller unit's state parameters under ideal conditions, enabling accurate control of the battery temperature while maintaining low overall system energy consumption. To achieve these state parameters, the solenoid valves to the target number of valves being opened are directly opened. Next, a corresponding preset control strategy is determined based on a comparison between the target number of valves being opened and a preset low-load threshold. The chiller unit's operating parameters are then adjusted according to this preset control strategy until the actual outlet water temperature is less than or equal to the target outlet water temperature. These operating parameters include at least one of the following: the speed of the water pump within the chiller unit, the frequency of the variable frequency compressor, and the opening degree of the electronic expansion valve. Compared to conventional constant flow and fixed frequency chiller units, this method allows the chiller unit to provide appropriate cooling capacity based on the number of solenoid valves being opened, achieving accurate control of the battery temperature while maintaining low overall system energy consumption. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] in:

[0036] Figure 1 This is a flowchart illustrating a chiller unit control method in one embodiment;

[0037] Figure 2 This is a schematic diagram of the chiller unit in one embodiment;

[0038] Figure 3 This is a schematic diagram illustrating the specific process for determining the target outlet water temperature and the target number of openings in the first embodiment.

[0039] Figure 4 This is a schematic diagram illustrating the specific process for determining the target outlet water temperature and the target number of openings in the second embodiment.

[0040] Figure 5 This is a flowchart illustrating the adjustment of the operating parameters of a chiller unit under the premise of executing a first control strategy in one embodiment.

[0041] Figure 6 This is a flowchart illustrating the adjustment of the operating parameters of a chiller unit under the premise of executing a second control strategy in one embodiment.

[0042] Figure 7 This is a schematic diagram of the control device of a chiller unit in one embodiment;

[0043] Figure 8 This is a structural block diagram of the chiller unit control equipment in one embodiment. Detailed Implementation

[0044] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0045] like Figure 1 As shown, Figure 1 This is a flowchart illustrating a chiller unit control method in one embodiment, applied to, for example... Figure 2 The chiller unit shown includes a refrigerant circulation system 1 and a water circulation system 2. The refrigerant circulation system 1 includes a variable frequency compressor 11, an outdoor fan 12, a condenser 13, an electronic expansion valve 14, and a plate heat exchanger 15. The water circulation system 2 includes the plate heat exchanger 15, a circulating water tank 21, a water pump 22, and N solenoid valves 23 (N>1).

[0046] The refrigeration principle of this chiller unit is as follows:

[0047] In the refrigerant circulation system 1, low-temperature and low-pressure refrigerant vapor enters from the suction port of the variable frequency compressor 11 and is compressed into high-temperature and high-pressure refrigerant vapor. Then, in the condenser 13, it exchanges heat with the ambient air through the external fan 12 and condenses into high-temperature and high-pressure refrigerant liquid. After passing through the electronic expansion valve 14 for throttling and pressure reduction, it enters the plate heat exchanger 15 to exchange heat with the refrigerant in the water system and evaporates into low-temperature and low-pressure refrigerant vapor, completing one cycle.

[0048] Within the water system circulation, the high-temperature refrigerant flowing out after passing through the battery swapping station exchanges heat with the refrigerant in the plate heat exchanger 15 to cool down before entering the buffer water tank. It is then pressurized by the water pump 22 and flows out through the partially opened solenoid valve 23, finally flowing through the battery module of the battery swapping station to cool the battery module.

[0049] In the aforementioned chiller unit, this embodiment connects the return port of water pump 22 to a buffer tank, and the buffer tank is positioned higher than water pump 22. This is because when the battery swapping station switches between different operating conditions, the adjustment of the variable frequency compressor 11 and water pump 22 can cause fluctuations in the chiller unit's outlet water temperature. Adding the buffer tank can alleviate this problem. In this embodiment, after setting up the buffer tank, since the buffer tank contains a certain amount of low-temperature water, even if the unit's capacity fluctuates, it will absorb a certain fluctuation amplitude. Especially under low-load operation conditions at the battery swapping station, it can reduce the frequent start-stop of the chiller unit and ensure the stability of the entire system. Furthermore, placing the buffer tank at a relatively high position within the entire water circulation system 2 can serve as a pressure stabilizer for the water circulation system 2 and prevent cavitation of water pump 22.

[0050] The steps provided by the chiller unit control method in this embodiment include:

[0051] S101 determines the target outlet water temperature of the chiller unit and the target number of solenoid valves to be opened in the chiller unit based on the current cooling load demand of the battery swapping station.

[0052] The required cooling load is the minimum cooling capacity necessary to maintain a constant temperature of the battery modules within the battery swapping station. The target outlet water temperature and the target number of open valves are the state parameters of the chiller unit under ideal conditions. If the chiller unit can output refrigerant at the target outlet water temperature and the solenoid valves for the target number of open valves are open, the cooling load requirement of the battery swapping station can be met.

[0053] In this embodiment, the target outlet water temperature and the target number of start-ups are determined by a strategy that minimizes the target number of start-ups while ensuring that the target outlet water temperature is within a reasonable range. This allows the chiller unit to operate under low load logic, i.e., the operation logic of s102-s103. Compared with the operation mode of traditional constant flow and fixed frequency chiller units, this can effectively reduce the problem of frequent start-ups and shutdowns of the chiller unit.

[0054] In one specific embodiment, such as Figure 3 As shown, the specific steps for determining the target outlet water temperature and the target number of openings are as follows:

[0055] s101A, set the temporary number of solenoid valves opened in the chiller unit to i = 1.

[0056] S101B calculates the provisional flow rate of the chiller unit based on the current provisional number of units in operation.

[0057] In steps s101A-s101B, to minimize the target number of valves opened, the number of valves opened is temporarily set to 1, i.e., the provisional number of valves opened i = 1. The number of solenoid valves opened determines the refrigerant flow rate through the battery module. Generally, the more solenoid valves opened, the greater the refrigerant flow rate through the battery module. Based on the preset formula corresponding to the above relationship in this step and the determined provisional number of valves opened, the provisional flow rate of the chiller unit can be calculated.

[0058] S101C calculates the provisional outlet water temperature of the chiller unit based on the cooling load demand and provisional flow rate.

[0059] Given that the cooling load demand is known, the smaller the provisional flow rate, the lower the provisional outlet water temperature should be. Based on the preset formula corresponding to the above relationship in this step, the determined cooling load demand, and the provisional flow rate, the provisional outlet water temperature can be calculated here.

[0060] Step s101D determines whether the provisional outlet water temperature is within the range that the chiller unit can provide. If the provisional outlet water temperature is not within the range that the chiller unit can provide, then set i = i + 1 and return to execute step s101B and subsequent steps. If the provisional outlet water temperature is within the range that the chiller unit can provide, then execute step s101E, setting the currently determined provisional opening quantity as the target opening quantity and the currently determined provisional outlet water temperature as the target outlet water temperature.

[0061] In other words, if the provisional outlet water temperature does not meet the outlet water temperature range limit, the provisional opening quantity i needs to be determined iteratively. If the provisional outlet water temperature meets the outlet water temperature range limit, the currently determined provisional opening quantity is taken as the target opening quantity, and the currently determined provisional outlet water temperature is taken as the target outlet water temperature. In this way, the most suitable target opening quantity and target outlet water temperature are found under the premise of meeting the cooling load demand.

[0062] In another specific embodiment, such as Figure 4 As shown, the specific steps for determining the target outlet water temperature and the target number of openings are as follows:

[0063] s101a, if the current flow demand of the battery swapping station is obtained, calculate the range of the number of solenoid valves to be opened in the chiller unit based on the flow demand, and take the smallest integer value within the range of the number of valves to be opened as the target number of valves to be opened.

[0064] The flow rate requirement refers to the minimum flow rate of refrigerant flowing through the battery module. In other words, in this specific embodiment, in addition to the limitation on the cooling load requirement, there is also a limitation on the flow rate requirement. As mentioned earlier, the number of solenoid valves that open determines the flow rate of refrigerant through the battery module. Generally, the larger the refrigerant flow rate through the battery module, the more solenoid valves need to be opened. Based on the preset formula corresponding to the relationship mentioned above in this step and the determined flow rate requirement, the range of opening numbers can be calculated. Assuming the calculated range of opening numbers is greater than or equal to 3.5, the target opening number is 4.

[0065] S101B calculates the target outlet water temperature of the chiller unit based on the cooling load demand and the target number of units to be turned on.

[0066] First, the available flow rate can be calculated based on the target number of switches. Then, given the cooling load demand, the smaller the available flow rate, the lower the target outlet water temperature should be. Based on the preset formula corresponding to the relationship mentioned above in this step and the calculated available flow rate, the target outlet water temperature can be calculated. In this way, the most suitable target number of switches and the target outlet water temperature can be found while meeting both the cooling load demand and the flow rate demand.

[0067] s102, open the solenoid valves of the target number of openings, and determine the corresponding preset control strategy based on the comparison between the target number of openings and the preset low load threshold.

[0068] In this embodiment, the preset control strategy includes a first control strategy for low-load operation and a second control strategy for normal operation. First, the target number of solenoid valves is opened. If the target number of openings is less than or equal to a preset low-load threshold 'a', it is determined that the chiller unit only needs to operate at a low load, and the first control strategy is executed. Conversely, if the target number of openings is greater than the preset low-load threshold 'a', it is determined that the current condition for low-load operation is not met, and the second control strategy is executed. Generally, the value of 'a' here is between 2 and 5.

[0069] s103 adjusts the operating parameters of the chiller unit according to the preset control strategy until the actual outlet water temperature of the chiller unit is less than or equal to the target outlet water temperature.

[0070] Understandably, referring to Figure 2 The flow rate of refrigerant through the solenoid valves in this chiller unit is controlled by a water pump. Therefore, to ensure the target number of solenoid valves are open and functioning correctly, in a specific embodiment, regardless of the chosen control strategy, the following steps must be performed to adjust the chiller unit's operating parameters:

[0071] 1. Based on the correspondence between the number of solenoid valves opened and the flow rate, determine the target water flow rate of the chiller unit according to the target number of valves opened;

[0072] If we assume that each solenoid valve can allow a flow rate of Q of refrigerant, then the relationship between the number of solenoid valves opened (n) and the flow rate is n*Q. Accordingly, given a target number of valves opened, the target water flow rate = target number of valves opened * Q.

[0073] 2. Control the water pump of the chiller to adjust the flow rate to match the target water flow rate.

[0074] For example, if the water pump is a variable frequency pump, with a current operating frequency of f1 and a current output water flow rate of Q1 (Q1 < target water flow rate), then after determining the target water flow rate, the flow rate can be adjusted by continuously increasing the current operating frequency f1 until Q1 = the target water flow rate, or the difference between Q1 and the target water flow rate is less than a preset flow rate difference. Alternatively, if the current operating frequency is f2 and the current output water flow rate is Q2 (Q2 > target water flow rate), then after determining the target water flow rate, the flow rate can be adjusted by continuously decreasing the current operating frequency f2 until Q2 = the target water flow rate, or the difference between Q2 and the target water flow rate is less than a preset flow rate difference.

[0075] In one specific embodiment, such as Figure 5 As shown, the operating parameters of the chiller unit are also adjusted through the following steps:

[0076] S103A, under the premise of executing the first control strategy, determines the target suction superheat based on the sum of the current suction superheat of the chiller unit and the preset value.

[0077] The compressor's suction superheat is calculated as: suction temperature - suction pressure corresponding to saturation temperature. Suction temperature refers to the temperature of the refrigerant when it enters the compressor. Suction pressure corresponding to saturation temperature refers to the refrigerant's evaporation saturation temperature. If there is no suction superheat, liquid carryover may occur, potentially causing liquid slugging during wet strokes and damaging the compressor. To avoid this, a certain suction superheat is required to ensure that only dry vapor enters the compressor.

[0078] Here, under the premise of implementing the first control strategy, low-load superheat adjustment is selected, that is, the sum of the current suction superheat of the chiller unit and the preset value is used as the target suction superheat. The preset value can be obtained in advance through experiments.

[0079] S103B adjusts the opening of the electronic expansion valve according to the target intake superheat.

[0080] The opening degree of the electronic expansion valve affects the saturation temperature corresponding to the suction temperature and suction pressure. The relationship between the electronic expansion valve opening degree and the corresponding saturation temperature can be pre-established through experiments. Based on this target suction superheat and the opening degree relationship, the required opening degree in S1032B can be calculated and adjusted. Under low-load conditions at the battery swapping station, adjusting the electronic expansion valve opening according to the normal superheat would lead to excessive cooling capacity, ultimately causing frequent system start-ups and shutdowns. However, the embodiment of this application adjusts the electronic expansion valve opening by adding a preset value to the normal superheat, i.e., through superheat compensation. This reduces the cooling capacity, decreases the inlet and outlet water temperature difference, and prevents the outlet water temperature from reaching the shutdown point, thus avoiding frequent system start-ups and shutdowns.

[0081] S103C controls the compressor of the chiller unit to operate at a preset minimum frequency.

[0082] This allows the chiller to provide matching cooling capacity based on the current low load of the battery swapping station, enabling the system to still accurately control the temperature of the batteries being charged and avoid excessive energy consumption.

[0083] In one specific embodiment, such as Figure 6 As shown, the operating parameters of the chiller unit are also adjusted through the following steps:

[0084] S103a, under the premise of implementing the second control strategy, adjust the opening of the electronic expansion valve according to the current suction superheat of the chiller unit.

[0085] Here, under the premise of implementing the second control strategy, normal superheat adjustment is performed. Since the opening degree of the electronic expansion valve affects the saturation temperature corresponding to the suction temperature and suction pressure, the opening degree relationship between the electronic expansion valve opening degree and the saturation temperature corresponding to the suction temperature and suction pressure can be constructed in advance through experiments. Then, based on the current suction superheat degree and this opening degree relationship, the required opening degree in S1031a can be calculated and adjusted.

[0086] S103b, determine the target cooling load of the chiller unit based on the target outlet water temperature and the actual outlet water temperature.

[0087] The actual outlet water temperature is the temperature at which the refrigerant currently flows through the battery modules of the battery swapping station to cool them. The target cooling load is the cooling load that the chiller unit should provide. When the actual outlet water temperature is greater than the target outlet water temperature, and the greater the difference between the actual and target outlet water temperatures, the greater the corresponding target cooling load should be.

[0088] S103c determines the target speed of the variable frequency compressor based on the target cooling load.

[0089] Specifically, the cooling load-speed relationship between the cooling load and speed that the variable frequency variable capacity compressor can provide can be established in advance through experiments. Then, the target speed can be calculated based on the target cooling load and the cooling load-speed relationship.

[0090] S103d, adjust the compression frequency of the variable frequency compressor according to the target speed until the actual outlet water temperature of the chiller unit is less than or equal to the target outlet water temperature.

[0091] Generally speaking, the higher the compression frequency set by the variable frequency compressor, the faster the speed of the variable frequency compressor should be. Based on the preset formula corresponding to the above relationship in this step and the determined target speed, the required compression frequency of the variable frequency compressor can be calculated and adjusted.

[0092] Next, the system makes adjustments based on the actual outlet water temperature of the chiller unit. If the actual outlet water temperature of the chiller unit is greater than the target outlet water temperature, the system continues to iterate and execute s103. If the actual outlet water temperature of the chiller unit is less than or equal to the target outlet water temperature, the system maintains the compression frequency of the variable frequency compressor. At this time, the actual cooling load provided by the chiller unit is exactly greater than or equal to the cooling load demand of the battery swapping station, which enables the system to achieve accurate control of the temperature of the battery being charged while maintaining low overall operating energy consumption.

[0093] It is evident that, compared to conventional constant flow and fixed frequency chiller control methods, the above-mentioned chiller control method can reduce the frequent start-stop of the chiller and also enable the system to achieve accurate control of the temperature of the rechargeable battery while maintaining low overall energy consumption.

[0094] In one embodiment, such as Figure 7 As shown, a chiller unit control device is proposed, which includes:

[0095] The parameter acquisition and setting module 701 is used to determine the target outlet water temperature of the chiller and the target number of solenoid valves to be opened in the chiller based on the current cooling load demand of the battery swapping station.

[0096] The control module 702 is used to open the solenoid valves of the target number of openings and determine the corresponding preset control strategy based on the comparison between the target number of openings and the preset low load threshold; and adjust the operating parameters of the chiller unit according to the preset control strategy until the actual outlet water temperature of the chiller unit is less than or equal to the target outlet water temperature; wherein, the operating parameters include at least one of the following: the speed of the water pump in the chiller unit, the frequency of the variable frequency compressor, and the opening degree of the electronic expansion valve.

[0097] In one embodiment, the control module 702 is specifically used to: determine the target water flow rate of the chiller unit based on the correspondence between the number of solenoid valves opened and the flow rate; and control the speed of the water pump to adjust the flow rate to match the target water flow rate.

[0098] In one embodiment, the control module 702 is specifically used to: determine the target suction superheat based on the sum of the current suction superheat of the chiller unit and a preset value, under the premise of executing the first control strategy; wherein, the first control strategy is the preset control strategy corresponding to when the target number of openings is less than or equal to a preset low load threshold; and adjust the opening degree of the electronic expansion valve according to the target suction superheat.

[0099] In one embodiment, the control module 702 is specifically used to control the compressor of the chiller unit to operate at a preset minimum frequency.

[0100] In one embodiment, the control module 702 is specifically used to: adjust the opening degree of the electronic expansion valve according to the current suction superheat of the chiller unit under the premise of executing the second control strategy; wherein, the second control strategy is the preset control strategy corresponding to when the target number of openings is greater than a preset low load threshold.

[0101] In one embodiment, the control module 702 is specifically used to: determine the target cooling load of the chiller unit based on the target outlet water temperature and the actual outlet water temperature; determine the target speed of the variable frequency compressor based on the target cooling load; and adjust the compression frequency of the variable frequency compressor based on the target speed until the actual outlet water temperature of the chiller unit is less than or equal to the target outlet water temperature.

[0102] In one embodiment, the parameter acquisition and setting module 701 is specifically used for: setting the temporary opening quantity i of the solenoid valve in the chiller unit to 1; calculating the temporary flow rate of the chiller unit based on the current temporary opening quantity; calculating the temporary outlet water temperature of the chiller unit based on the cooling load demand and the temporary flow rate; determining whether the temporary outlet water temperature is within the range of outlet water temperatures that the chiller unit can provide; if the temporary outlet water temperature is not within the range of outlet water temperatures that the chiller unit can provide, then setting i to i+1, returning to execute the step of calculating the temporary flow rate of the chiller unit based on the current temporary opening quantity and subsequent steps; if the temporary outlet water temperature is within the range of outlet water temperatures that the chiller unit can provide, then taking the currently determined temporary opening quantity as the target opening quantity and the currently determined temporary outlet water temperature as the target outlet water temperature.

[0103] Figure 8 An internal structural diagram of the chiller unit control equipment in one embodiment is shown. Figure 8As shown, the chiller control device includes a processor, a memory, and a network interface connected via a system bus. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores an operating system and may also store a computer program. When executed by the processor, this computer program enables the processor to implement the chiller control method. The internal memory may also store a computer program, which, when executed by the processor, enables the processor to execute the chiller control method. Those skilled in the art will understand that… Figure 8 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the chiller control equipment to which the present application is applied. The specific chiller control equipment may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0104] A chiller unit control device includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it performs the following steps: obtaining the current cooling load demand of the battery swapping station; determining the target outlet water temperature of the chiller unit and the target number of solenoid valves to be opened in the chiller unit based on the cooling load demand; opening the solenoid valves to the target number of openings; and determining a corresponding preset control strategy based on a comparison between the target number of openings and a preset low-load threshold; and adjusting the operating parameters of the chiller unit according to the preset control strategy until the actual outlet water temperature of the chiller unit is less than or equal to the target outlet water temperature.

[0105] A computer-readable storage medium storing a computer program, which, when executed by a processor, performs the following steps: obtaining the current cooling load demand of a battery swapping station; determining the target outlet water temperature of a chiller unit and the target number of solenoid valves to be opened within the chiller unit based on the cooling load demand; opening the solenoid valves to the target number of openings; and determining a corresponding preset control strategy based on a comparison between the target number of openings and a preset low-load threshold; and adjusting the operating parameters of the chiller unit according to the preset control strategy until the actual outlet water temperature of the chiller unit is less than or equal to the target outlet water temperature.

[0106] It should be noted that the above-mentioned chiller control method, device, equipment and computer-readable storage medium belong to the same general inventive concept, and the contents of the embodiments of the chiller control method, device, equipment and computer-readable storage medium are applicable to each other.

[0107] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. This program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), RAMbus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and RAMbus dynamic RAM (RDRAM), etc.

[0108] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0109] The above embodiments merely illustrate several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A chiller control method, comprising: The method comprises: determining a target outlet water temperature of the water chiller and a target opening number of electromagnetic valves in the water chiller according to a current cold load demand of the battery swap station; wherein the water chiller comprises a refrigerant circulation system and a water circulation system, in the water circulation system, high-temperature cold carrier flowing out after the battery swap station exchanges heat with refrigerant in a plate heat exchanger to be cooled, and then enters a buffer tank, and then flows out from the partially opened electromagnetic valves after being pressurized by a water pump; opening the electromagnetic valves with the target opening number, and determining a corresponding preset control strategy based on a comparison relationship between the target opening number and a preset low-load threshold; adjusting working parameters of the water chiller according to the preset control strategy until an actual outlet water temperature of the water chiller is less than or equal to the target outlet water temperature; wherein the working parameters comprise at least one of a rotating speed of the water pump, a frequency of the variable frequency compressor, and an opening degree of the electronic expansion valve in the water chiller; the adjusting working parameters of the water chiller according to the preset control strategy comprises: on the premise of executing a first control strategy, determining a target suction superheat degree according to a sum of a current suction superheat degree of the water chiller and a preset value; wherein the first control strategy is a preset control strategy corresponding to a case that the target opening number is less than or equal to the preset low-load threshold; adjusting the opening degree of the electronic expansion valve according to the target suction superheat degree; the determining a target outlet water temperature of the water chiller and a target opening number of electromagnetic valves in the water chiller according to a current cold load demand of the battery swap station comprises: letting a temporary opening number i of the electromagnetic valves in the water chiller be 1, calculating a temporary flow of the water chiller according to the current temporary opening number; calculating a temporary outlet water temperature of the water chiller according to the cold load demand and the temporary flow, and judging whether the temporary outlet water temperature is within an outlet water temperature range that can be provided by the water chiller; if the temporary outlet water temperature is not within the outlet water temperature range that can be provided by the water chiller, letting i=i+1, and returning to execute the step of calculating the temporary flow of the water chiller according to the current temporary opening number and subsequent steps; if the temporary outlet water temperature is within the outlet water temperature range that can be provided by the water chiller, taking the current determined temporary opening number as the target opening number, and taking the current determined temporary outlet water temperature as the target outlet water temperature.

2. The method of claim 1, wherein, the adjusting working parameters of the water chiller according to the preset control strategy comprises: determining a target water flow of the water chiller according to the target opening number based on a corresponding relationship between the opening number of the electromagnetic valves and the flow; controlling the rotating speed of the water pump to perform flow adjustment matching the target water flow.

3. The method of claim 1, wherein, after the adjusting the opening degree of the electronic expansion valve according to the target suction superheat degree, further comprising: controlling the compressor of the water chiller to operate at a preset minimum frequency.

4. The method of claim 1, wherein, the adjusting working parameters of the water chiller according to the preset control strategy comprises: Adjusting the opening degree of the electronic expansion valve according to the current suction gas superheat of the water chiller under the premise of executing the second control strategy; wherein the second control strategy is a preset control strategy corresponding to a case that the target opening number is greater than the preset low-load threshold.

5. The method of claim 4, wherein, After the step of adjusting the opening degree of the electronic expansion valve according to the current suction gas superheat of the water chiller, the method further comprises: Determining a target cooling load of the water chiller according to the target outlet water temperature and the actual outlet water temperature; Determining a target rotating speed of the variable frequency compressor according to the target cooling load; Adjusting the compression frequency of the variable frequency compressor according to the target rotating speed until the actual outlet water temperature of the water chiller is less than or equal to the target outlet water temperature.

6. A water chiller control device characterized by comprising: The device comprises: A parameter acquisition and setting module configured to determine a target outlet water temperature of the water chiller and a target opening number of electromagnetic valves in the water chiller according to a current cooling load demand of the battery swap station; wherein the water chiller comprises a refrigerant circulation system and a water circulation system, and in the water circulation system, high-temperature cold carrier flowing out after the battery swap station exchanges heat with refrigerant in a plate heat exchanger to be cooled and then enters a buffer tank, and is pressurized by a water pump and flows out from the partially opened electromagnetic valves; A control module configured to open the electromagnetic valves with the target opening number, and determine a preset control strategy corresponding to a comparison relationship between the target opening number and a preset low-load threshold; and adjust working parameters of the water chiller according to the preset control strategy until the actual outlet water temperature of the water chiller is less than or equal to the target outlet water temperature; wherein the working parameters comprise at least one of a rotating speed of a water pump, a frequency of a variable frequency compressor, and an opening degree of an electronic expansion valve in the water chiller; The control module is specifically configured to: Determine a target suction gas superheat according to a sum of the current suction gas superheat of the water chiller and a preset value under the premise of executing a first control strategy; wherein the first control strategy is a preset control strategy corresponding to a case that the target opening number is less than or equal to the preset low-load threshold; Adjust the opening degree of the electronic expansion valve according to the target suction gas superheat; The parameter acquisition and setting module is specifically configured to set a temporary opening number i=1 of the electromagnetic valves in the water chiller, calculate a temporary flow of the water chiller according to the current temporary opening number; Calculate a temporary outlet water temperature of the water chiller according to the cooling load demand and the temporary flow, and determine whether the temporary outlet water temperature is within a range of outlet water temperatures that the water chiller can provide; If the temporary outlet water temperature is not within the range of outlet water temperatures that the water chiller can provide, set i=i+1, and return to execute the step of calculating the temporary flow of the water chiller according to the current temporary opening number and subsequent steps; If the temporary outlet water temperature is within the range of outlet water temperatures that the water chiller can provide, set the current determined temporary opening number as the target opening number, and set the current determined temporary outlet water temperature as the target outlet water temperature.

7. A computer readable storage medium storing a computer program, characterized in that, The computer program, when executed by a processor, causes the processor to perform the steps of the method of any one of claims 1 to 5.

8. A water chiller control device comprising a memory and a processor, wherein, The memory stores a computer program which, when executed by the processor, causes the processor to perform the steps of the method of any one of claims 1 to 5.

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