A method and device for dynamic thermal management of energy storage cells

Abstract

This invention discloses a dynamic thermal management method and device for energy storage cells, relating to the field of energy storage BMS technology. The method includes: after the energy storage system is initialized, calculating a first cell temperature difference parameter according to the cell parameters corresponding to a first preset time step managed in the system and the current cell parameters; when it is determined that the water chiller in the energy storage system is in a cooling state, determining the cooling target temperature change according to the first cell temperature difference parameter; when the first cell temperature difference parameter does not meet the preset control conditions, determining the cooling target temperature change according to the second cell parameters corresponding to a second preset time step and the current cell parameters; adjusting the cooling target temperature according to the cooling target temperature change to adjust the energy storage cell temperature, thereby reducing the continuous power loss of the liquid cooling unit in maintaining the cell temperature.

Description

Technical Field

[0001] This invention relates to the field of energy storage BMS (Battery Management System) technology, and in particular to a method and apparatus for dynamic thermal management of energy storage cells. Background Technology

[0002] With the rapid expansion of the new energy storage industry and the continuous iteration and upgrading of energy storage technologies, the installed capacity and market penetration rate of various energy storage systems are steadily increasing. Application scenarios are becoming increasingly diversified, and the scope of deployment is expanding. Distributed and large-scale energy storage equipment has widely covered the grid side, user side, and new energy supporting scenarios. As the core energy carrier of energy storage BMS, the working stability, cycle life, and operational safety of energy storage cells highly depend on precise temperature control. Cell thermal management has thus become one of the key core technologies for the research and development and implementation of energy storage BMS.

[0003] Under complex operating conditions such as frequent charging and discharging, rate fluctuations, changes in ambient temperature, and dense heat dissipation coupling in clusters, energy storage cells are prone to problems such as excessive local temperature rise, widening cell temperature differences, and heat accumulation, which seriously affect system safety and service life. Therefore, the thermal management control strategy of the energy storage BMS during actual operation must take into account the dual objectives of safety, consistency, and energy saving: on the one hand, it must monitor the temperature of individual cells and clusters in real time, dynamically balance heat dissipation requirements, and ensure that the cells are always maintained in the optimal temperature range for safety and efficiency under all operating conditions, suppressing the risk of thermal runaway and ensuring the consistency of cell charging and discharging performance with the overall cluster temperature; on the other hand, it must abandon the existing energy storage cell thermal management solution's control strategy of constant output of liquid cooling units to control cell temperature during energy storage system operation. This constant output control strategy consumes a lot of power from the water chiller and cannot meet the requirements of high efficiency and energy saving. Summary of the Invention

[0004] The purpose of this invention is to provide a dynamic thermal management method and device for energy storage cells, which can solve the above-mentioned problems existing in the prior art.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution: This invention provides a dynamic thermal management method for energy storage cells, wherein the method includes: After the energy storage system is initialized, the first cell temperature difference parameter is calculated according to the first cell parameters corresponding to the first preset time step managed in the system and the current cell parameters collected. The first cell parameters include: the first maximum cell temperature value and the first average cell temperature value; the first cell temperature difference parameter includes: the first maximum cell temperature difference and the first average cell temperature difference. When it is determined that the water turbine in the energy storage system is in a cooling state, the target temperature change is determined according to the first cell temperature difference parameter. If the temperature difference parameter of the first cell does not meet the preset control conditions, the change in the target cooling temperature is determined according to the second cell parameter corresponding to the second preset time step managed in the system and the current cell parameter collected. The target cooling temperature is adjusted based on the change in the target cooling temperature to adjust the temperature of the energy storage cell.

[0006] Optionally, before the step of calculating the first cell temperature difference parameter according to the first cell parameter corresponding to the first preset time step managed in the system and the collected current cell parameter after the energy storage system initialization is completed, the method further includes: Determine whether the initialization flag of the energy storage system indicates that initialization has been completed; If not, initiate the energy storage system initialization process and set the timing variable to 0; Set the initial value of the target cooling temperature to the preset temperature value; Obtain the parameters of the first battery cell corresponding to the first preset time step managed in the system; Obtain the second cell parameters corresponding to the second preset time step managed in the system.

[0007] Optionally, the step of determining the target temperature change based on the first cell temperature difference parameter when it is determined that the water turbine in the energy storage system is in a cooling state includes: If it is determined that the water turbine in the energy storage system is in a cooling state, it is determined whether at least one of the first maximum cell temperature difference and the first average cell temperature difference is greater than a first value; if so, the target cooling temperature change is determined to be a decrease of a second value. If not, determine whether at least one of the first maximum cell temperature difference and the first average cell temperature difference is less than the third value; if yes, determine that the change in the cooling target temperature is to increase the second value; wherein, the first value is a positive number and the third value is a negative number; if not, determine that the preset control conditions are not met.

[0008] Optionally, the step of determining the change in the cooling target temperature according to the second cell parameters corresponding to the second preset time step and the collected current cell parameters includes: The second cell temperature difference parameter is calculated based on the second cell parameters corresponding to the second preset time step and the collected current cell parameters. The second cell temperature difference parameter includes: the second maximum cell temperature difference and the second average cell temperature difference; the second cell parameters include: the second maximum cell temperature value and the second average cell temperature value. Based on the second maximum cell temperature value and the second maximum cell temperature difference, determine the first temperature change corresponding to the second maximum cell temperature value; Based on the second average cell temperature value and the second average cell temperature difference, determine the second temperature change corresponding to the second average cell temperature value; The minimum of the first temperature change and the second temperature change is taken as the target temperature change for cooling.

[0009] Optionally, the step of determining the second temperature change corresponding to the second average cell temperature value based on the second average cell temperature value and the second average cell temperature difference includes: Determine whether the second average cell temperature value is lower than the average temperature value when cooling is turned on; If not, determine the first temperature range to which the second average cell temperature value belongs, and determine the corresponding column value in the first preset table based on the first temperature range; Determine the first temperature difference range to which the second average cell temperature difference belongs, and determine the corresponding row value in the first preset table based on the first temperature difference range; Based on the row value and the column value, find the second temperature change corresponding to the second average cell temperature value in the first preset table.

[0010] Optionally, the step of determining the first temperature change corresponding to the second maximum cell temperature value based on the second maximum cell temperature value and the second maximum cell temperature difference includes: Determine whether the second maximum cell temperature value is less than the maximum temperature value when the cooling is turned on; If not, determine the second temperature range to which the second maximum cell temperature value belongs, and determine the corresponding column value in the second preset table based on the second temperature range; Determine the second temperature difference range to which the second maximum cell temperature difference belongs, and determine the corresponding row value in the second preset table based on the second temperature difference range; Based on the row value and the column value, find the first temperature change corresponding to the second maximum cell temperature value in the second preset table.

[0011] Optionally, the method further includes: Determine whether the change in the target cooling temperature is 0; If the change in the target cooling temperature is not 0, then the first cell parameter corresponding to the first preset time step managed in the system is updated to the current cell parameter, and the second cell parameter corresponding to the second preset time step is updated to the current cell parameter. If the change in the target cooling temperature is 0, then determine whether the time since the first cell parameter was not updated has reached the first preset time step; if yes, then update the first cell parameter to the current cell parameter; if no, then do not update the first cell parameter. If the change in the target cooling temperature is 0, then determine whether the time since the second cell parameter was not updated has reached the second preset time step; if yes, then update the second cell parameter to the current cell parameter; if no, then do not update the second cell parameter.

[0012] This invention also provides a dynamic thermal management device for energy storage cells, wherein the device includes: The calculation module is used to calculate the first cell temperature difference parameter according to the first cell parameters corresponding to the first preset time step managed in the system after the energy storage system is initialized. The first cell parameters include: a first maximum cell temperature value and a first average cell temperature value; the first cell temperature difference parameter includes: a first maximum cell temperature difference and a first average cell temperature difference. The first determining module is used to determine the target temperature change of cooling according to the first cell temperature difference parameter when it is determined that the water turbine in the energy storage system is in a cooling state. The second determining module is used to determine the change in cooling target temperature according to the second cell parameter corresponding to the second preset time step managed in the system and the collected current cell parameter when the first cell temperature difference parameter does not meet the preset control conditions. The adjustment module is used to adjust the cooling target temperature according to the change in the cooling target temperature, so as to adjust the temperature of the energy storage cell.

[0013] Optionally, the device further includes an initialization module for: Determine whether the initialization flag of the energy storage system indicates that initialization has been completed; If not, initiate the energy storage system initialization process and set the timing variable to 0; Set the initial value of the target cooling temperature to the preset temperature value; Obtain the parameters of the first battery cell corresponding to the first preset time step managed in the system; Obtain the second cell parameters corresponding to the second preset time step managed in the system to complete the energy storage system initialization.

[0014] Optionally, the first determining module is specifically used for: If it is determined that the water turbine in the energy storage system is in a cooling state, it is determined whether at least one of the first maximum cell temperature difference and the first average cell temperature difference is greater than a first value; if so, the target cooling temperature change is determined to be a decrease of a second value. If not, determine whether at least one of the first maximum cell temperature difference and the first average cell temperature difference is less than the third value; if yes, determine that the change in the cooling target temperature is to increase the second value; wherein, the first value is a positive number and the third value is a negative number; if not, determine that the preset control conditions are not met.

[0015] Optionally, the second determining module includes: The first submodule is used to calculate the second cell temperature difference parameter according to the second cell parameters corresponding to the second preset time step and the collected current cell parameters, wherein the second cell temperature difference parameter includes: the second maximum cell temperature difference and the second average cell temperature difference; the second cell parameters include: the second maximum cell temperature value and the second average cell temperature value; The second submodule is used to determine the first temperature change corresponding to the second maximum cell temperature value based on the second maximum cell temperature value and the second maximum cell temperature difference. The third submodule is used to determine the second temperature change corresponding to the second average cell temperature value based on the second average cell temperature value and the second average cell temperature difference. The fourth submodule is used to take the minimum value between the first temperature change and the second temperature change as the target temperature change for cooling.

[0016] Optionally, the third submodule is specifically used for: Determine whether the second average cell temperature value is lower than the average temperature value when cooling is turned on; If not, determine the first temperature range to which the second average cell temperature value belongs, and determine the corresponding column value in the first preset table based on the first temperature range; Determine the first temperature difference range to which the second average cell temperature difference belongs, and determine the corresponding row value in the first preset table based on the first temperature difference range; Based on the row value and the column value, find the second temperature change corresponding to the second average cell temperature value in the first preset table.

[0017] Optionally, the second submodule is specifically used for: Determine whether the second maximum cell temperature value is less than the maximum temperature value when the cooling is turned on; If not, determine the second temperature range to which the second maximum cell temperature value belongs, and determine the corresponding column value in the second preset table based on the second temperature range; Determine the second temperature difference range to which the second maximum cell temperature difference belongs, and determine the corresponding row value in the second preset table based on the second temperature difference range; Based on the row value and the column value, find the first temperature change corresponding to the second maximum cell temperature value in the second preset table.

[0018] Optionally, the device further includes an update module for: Determine whether the change in the target cooling temperature is 0; If the change in the target cooling temperature is not 0, then the first cell parameter corresponding to the first preset time step managed in the system is updated to the current cell parameter, and the second cell parameter corresponding to the second preset time step is updated to the current cell parameter. If the change in the target cooling temperature is 0, then determine whether the time since the first cell parameter was not updated has reached the first preset time step; if yes, then update the first cell parameter to the current cell parameter; if no, then do not update the first cell parameter. If the change in the target cooling temperature is 0, then determine whether the time since the second cell parameter was not updated has reached the second preset time step; if yes, then update the second cell parameter to the current cell parameter; if no, then do not update the second cell parameter.

[0019] This invention also provides an electronic device, including a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus; the memory is used to store computer programs; and the processor, when executing the program stored in the memory, implements any of the above-described dynamic thermal management methods for energy storage cells.

[0020] The dynamic thermal management scheme for energy storage cells disclosed in this invention involves the following steps: After the energy storage system is initialized, a first cell temperature difference parameter is calculated based on the first cell parameters corresponding to the first preset time step managed in the system. If the water chiller in the energy storage system is determined to be in cooling mode, the target cooling temperature change is determined based on the first cell temperature difference parameter. If the first cell temperature difference parameter does not meet the preset control conditions, the target cooling temperature change is determined based on the second cell parameters corresponding to the second preset time step managed in the system and the collected current cell parameters. The target cooling temperature is then adjusted based on the target cooling temperature change to adjust the energy storage cell temperature. This scheme ensures that the cells remain within a safe and efficient temperature range during the operation of the energy storage system. Furthermore, the proposed dynamic thermal management algorithm avoids continuous power loss from the liquid cooling unit in maintaining cell temperature. While maintaining the cell temperature within a reasonable range, it also reduces the overall output power of the liquid cooling unit, improving the overall efficiency of the energy storage system and reducing its operating costs. Attached Figure Description

[0021] Figure 1This is a flowchart illustrating the steps of a dynamic thermal management method for energy storage cells according to an embodiment of this application; Figure 2 This is a flowchart illustrating the steps of a method for determining a second temperature change according to an embodiment of this application; Figure 3 This is a flowchart illustrating the steps of a method for determining a first temperature change according to an embodiment of this application; Figure 4 This is a structural block diagram illustrating a dynamic thermal management device for energy storage cells according to an embodiment of this application. Detailed Implementation

[0022] To make the technical problems, technical solutions and advantages of the present invention clearer, a detailed description will be given below in conjunction with the accompanying drawings and specific embodiments.

[0023] The dynamic thermal management method for energy storage cells provided in this application will be described in detail below with reference to the accompanying drawings, through specific embodiments and application scenarios.

[0024] As attached Figure 1 As shown, the dynamic thermal management method for energy storage cells in this application includes the following steps: Step 101: After the energy storage system is initialized, calculate the first cell temperature difference parameter according to the first cell parameter corresponding to the first preset time step managed in the system and the current cell parameter collected.

[0025] During the operation of an energy storage system (also known as a battery management system), the battery cells need to be maintained within a safe and efficient optimal temperature range. This is achieved by controlling the temperature range of the battery cells using equipment such as liquid chillers. However, the constant output control strategy of the liquid chillers at constant battery cell temperature consumes a significant amount of power. Therefore, this application provides a non-constant processing control strategy for dynamic thermal management of the energy storage battery cells. The dynamic thermal management method for energy storage battery cells provided in this application relies on intelligent dynamic control logic, rationally linking temperature control equipment such as liquid chillers, and adjusting cooling power, start-stop strategies, and operating load as needed. This minimizes the ineffective energy consumption of the temperature control system, effectively reducing the overall operation and maintenance costs and comprehensive energy consumption of the energy storage power station, and achieving a two-way synergy between safe and stable operation and high-efficiency energy saving in the energy storage system.

[0026] The first cell parameters include: the first maximum cell temperature value and the first average cell temperature value. The first cell temperature difference parameters include: the first maximum cell temperature difference and the first average cell temperature difference.

[0027] When calculating the first cell temperature difference parameter based on the first cell parameters and the collected current cell parameters, the difference between the collected maximum cell temperature value at the current moment and the first maximum cell temperature value can be obtained to get the first maximum cell voltage temperature difference; the difference between the collected average cell temperature value at the current moment and the first average cell temperature value can be calculated to get the first average cell temperature difference.

[0028] In this embodiment of the application, after the energy storage system is powered on, it determines whether initialization has been completed by judging the initialization flag. If it has not been completed, the initialization process is executed. An optional initialization process is as follows: Determine if the initialization flag of the energy storage system indicates that initialization is complete; if not, start the energy storage system initialization process and set the timing variable to 0; set the initial value of the cooling target temperature to the preset temperature value; obtain the first cell parameter corresponding to the first preset time step managed in the system; obtain the second cell parameter corresponding to the second preset time step managed in the system.

[0029] Setting the timing variable to 0 indicates the start of a new timing cycle. In the specific implementation, the timing variable controlled by the first preset time step is set to 0, and the timing variable controlled by the second preset time step is also set to 0. The first preset time step is less than the second preset time step. The specific values ​​of the first and second preset time steps can be flexibly set by those skilled in the art, and this embodiment does not impose specific limitations on them. For example, the first preset time step can be set to 1 minute, 2 minutes, or 3 minutes, and the second preset time step can be set to 5 minutes, 6 minutes, or 10 minutes, etc. The preset temperature value can be flexibly configured via a host computer, and the specific value can also be flexibly configured according to system performance and user needs. This embodiment does not impose specific limitations on them; for example, the preset temperature value can be set to 22℃.

[0030] The energy storage system collects cell parameters every preset time interval, such as 1 second. Based on the currently collected cell parameters and the cell parameters corresponding to the first preset time step and the second preset time step managed by the system, dynamic thermal management of the cells is performed. For example, if the maximum and average cell temperature values ​​are updated at time t0, at time t0+1s, the maximum and average cell temperature differences are calculated by subtracting these values ​​from those at time t0. Then, a threshold is determined to be triggered. If the threshold is triggered, the maximum and average cell temperature values ​​are updated again.

[0031] Step 102: If it is determined that the water turbine in the energy storage system is in a cooling state, determine the target temperature change of cooling according to the temperature difference parameter of the first cell.

[0032] Determine whether the water chiller in the energy storage system is in cooling mode. If yes, proceed to step 102 and subsequent steps; otherwise, exit the cooling target temperature control mode and end the process.

[0033] In one optional embodiment, when it is determined that the water turbine in the energy storage system is in a cooling state, determining the target temperature change based on the first cell temperature difference parameter may include the following sub-steps: Sub-step 1: If it is determined that the water turbine in the energy storage system is in a cooling state, determine whether at least one of the first maximum cell temperature difference and the first average cell temperature difference is greater than the first value; if so, determine that the cooling target temperature change is to decrease the second value.

[0034] The specific values ​​of the first and second values ​​can be flexibly set by those skilled in the art, and the embodiments of this application do not impose specific limitations on them. For example, the first value can be set to +0.2℃, and the second value can be set to 1.

[0035] Sub-step 2: If not, determine whether at least one of the first maximum cell temperature difference and the first average cell temperature difference is less than the third value; if yes, determine that the change in the cooling target temperature is to increase the second value.

[0036] The first value is positive and the third value is negative; otherwise, it is determined that the preset control conditions are not met.

[0037] The specific value of the third value can be flexibly set by those skilled in the art, and the embodiments of this application do not impose specific restrictions on it. For example, the third value is set to -0.3℃.

[0038] Sub-steps 1 and 2 are processes for determining the change in the target cooling temperature based on the first cell temperature difference parameter corresponding to the first preset time step. If the first cell temperature difference parameter corresponding to the first preset time step does not meet the preset control conditions, the adjustment time span needs to be increased, and the change in the target cooling temperature is determined based on the second cell parameter corresponding to the second preset time step.

[0039] If the first maximum cell temperature difference and the first average cell temperature difference calculated according to the first cell parameters corresponding to the first preset time step do not meet the judgment conditions set in sub-steps 2 and 3, it is determined that the preset control conditions are not met.

[0040] Step 103: If the temperature difference parameter of the first cell does not meet the preset control conditions, determine the change in the target cooling temperature according to the second cell parameter corresponding to the second preset time step and the collected current cell parameter.

[0041] In one optional embodiment, determining the change in the target cooling temperature according to the second cell parameters corresponding to the second preset time step and the collected current cell parameters may include the following sub-steps: Sub-step 1: Calculate the temperature difference parameter of the second cell according to the second cell parameters corresponding to the second preset time step and the current cell parameters collected; The second cell temperature difference parameter includes: the second maximum cell temperature difference and the second average cell temperature difference; the second cell parameter includes: the second maximum cell temperature value and the second average cell temperature value. The calculation method for the second cell temperature difference parameter is the same as that for the first cell temperature difference parameter, and will not be repeated here.

[0042] Sub-step 2: Based on the second maximum cell temperature value and the second maximum cell temperature difference, determine the first temperature change corresponding to the second maximum cell temperature value; Sub-step 3: Based on the second average cell temperature value and the second average cell temperature difference, determine the second temperature change corresponding to the second average cell temperature value; Sub-step 4: Take the minimum of the first temperature change and the second temperature change as the target temperature change for cooling.

[0043] A feasible method for determining the second temperature change corresponding to the second average cell temperature value based on the second average cell temperature value and the second average cell temperature difference is as follows: Figure 2 As shown, it may specifically include the following sub-steps: S31: Determine whether the second average cell temperature value is lower than the average temperature value when cooling is turned on.

[0044] If not, then execute S32; if yes, then determine that the second temperature change corresponding to the second average cell temperature value is 0.

[0045] The specific value of the average temperature when the cooling is turned on can be flexibly set by those skilled in the art, and no specific restrictions are imposed on this in the embodiments of this application.

[0046] S32: If not, determine the first temperature range to which the second average cell temperature value belongs, and determine the corresponding column value in the first preset table based on the first temperature range.

[0047] In actual implementation, multiple temperature ranges and their corresponding column values ​​in the table can be preset in the system. In S32, the second average cell temperature value first corresponds to the first temperature range, and then the column value corresponding to the first temperature range is determined according to the correspondence between each temperature range and the column value.

[0048] For example, the correspondence between temperature ranges and column values ​​can be set as follows: [30, 33.8) corresponds to column value 0; [34, 35.5) corresponds to column value 1; [35.7, 37.5) corresponds to column value 2; [37.7, 38.5) corresponds to column value 3; [38.7, +∞) corresponds to column value 4; other average cell temperature values ​​correspond to column value 5. That is, if the average cell temperature value does not match the above temperature range, it is considered to belong to other cases and corresponds to column value 5.

[0049] S33: Determine the first temperature difference range to which the second average cell temperature difference belongs, and determine the corresponding row value in the first preset table based on the first temperature difference range.

[0050] In actual implementation, multiple temperature difference ranges can be preset in the system to correspond to the row values ​​in the table. In S33, the first temperature difference range corresponding to the second average cell temperature difference is first determined, and then the row value corresponding to the first temperature difference range is determined according to the correspondence between each temperature difference range and the row value.

[0051] For example, the correspondence between temperature difference range and row value can be set as follows: (-∞, -0.5) corresponds to row value 0; [-0.5, -0.1) corresponds to row value 1; [-0.1, 0.1) corresponds to row value 2; (0.1, 0.5] corresponds to row value 3; (0.5, +∞) corresponds to row value 4.

[0052] S34: Based on the row and column values, find the second temperature change corresponding to the second average cell temperature value in the first preset table.

[0053] The first preset table contains multiple rows and columns of cells, each cell corresponding to a temperature change. Once the rows and columns are determined, the second temperature change can be accurately located within the first preset table.

[0054] A feasible method for determining the first temperature change corresponding to the maximum cell temperature value based on the maximum cell temperature value and the maximum cell temperature difference included in the cell parameters is as follows: Figure 3 As shown, it may specifically include the following sub-steps: S21: Determine whether the second maximum cell temperature is less than the maximum temperature value when cooling is turned on.

[0055] The specific value of the maximum temperature for cooling activation can be flexibly set by those skilled in the art, and no specific restrictions are imposed on this in the embodiments of this application.

[0056] If not, then execute S22; if yes, then determine that the first temperature change corresponding to the second maximum cell temperature value is 0.

[0057] S22: If not, determine the second temperature range to which the second maximum cell temperature value belongs, and determine the corresponding column value in the second preset table based on the second temperature range.

[0058] In actual implementation, multiple temperature ranges and their corresponding column values ​​in the table can be preset in the system. In S22, the second maximum cell temperature value is first determined to correspond to the second temperature range, and then the column value corresponding to the second temperature range is determined according to the correspondence between each temperature range and the column value.

[0059] For example, the correspondence between temperature ranges and column values ​​can be set as follows: [34, 35.8) corresponds to column value 0; [36, 37) corresponds to column value 1; [37.2, 38.2) corresponds to column value 2; [38.4, 40) corresponds to column value 3; [40.2, +∞) corresponds to column value 4; if the maximum temperature value does not match any of the above temperature ranges, it is considered to belong to other cases and corresponds to column value 5.

[0060] S23: Determine the second temperature difference range to which the second maximum cell temperature difference belongs, and determine the corresponding row value in the second preset table based on the second temperature difference range.

[0061] In actual implementation, multiple temperature difference ranges can be preset in the system and correspond to the row values ​​in the table. In S23, the second maximum cell temperature difference is first determined to correspond to the second temperature difference range, and then the row value corresponding to the second temperature difference range is determined according to the correspondence between each temperature difference range and the row value.

[0062] For example, the correspondence between temperature difference range and row value can be set as follows: (-∞, -0.5) corresponds to row value 0; [-0.5, -0.1) corresponds to row value 1; [-0.1, 0.1) corresponds to row value 2; (0.1, 0.5] corresponds to row value 3; (0.5, +∞) corresponds to row value 4.

[0063] S24: Based on the row and column values, find the first temperature change corresponding to the second maximum cell temperature value in the second preset table.

[0064] The second preset table contains multiple rows and columns of cells, each cell corresponding to a temperature change. After determining the rows and columns, the first temperature change can be accurately located in the second preset table.

[0065] It should be noted that the first preset table and the second preset table can be the same table or two independent tables. This application embodiment does not impose specific restrictions on this.

[0066] Step 104: Adjust the cooling target temperature according to the change in cooling target temperature to adjust the temperature of the energy storage cell.

[0067] After determining the change in the target cooling temperature, it is checked whether the change is 0. If it is 0, it means that no adjustment to the target cooling temperature is needed; if it is not 0, the change in target cooling temperature needs to be accumulated based on the target cooling temperature. In a preferred embodiment, the accumulated target cooling temperature can also be limited to 18-28℃. It should be noted that the specific range of the limit is not limited to 18-28℃, and the limit range can be flexibly set by those skilled in the art.

[0068] If the change in the target cooling temperature is not zero, the first cell parameters corresponding to the first preset time step managed in the system and the second cell parameters corresponding to the second preset time step managed in the system need to be updated. If the change in the target cooling temperature is not zero, the first cell parameters corresponding to the first preset time step managed in the system are updated to the current cell parameters, and the second cell parameters corresponding to the second preset time step are updated to the current cell parameters. Specifically, the timer corresponding to the first preset time step is cleared, the first average cell temperature value in the first cell parameters is updated to the current average cell temperature value, and the first maximum cell temperature value in the first cell parameters is updated to the current maximum cell temperature value. The timer corresponding to the second preset time step is cleared, the second average cell temperature value in the second cell parameters is updated to the current average cell temperature value, and the maximum cell temperature value in the second cell parameters is updated to the current maximum cell temperature value.

[0069] If the change in the target cooling temperature is 0, it is determined whether the time since the first cell parameter was not updated has reached a first preset time step; if yes, the first cell parameter is updated to the current cell parameter; if no, the first cell parameter is not updated. If the change in the target cooling temperature is 0, it is determined whether the time since the second cell parameter was not updated has reached a second preset time step; if yes, the second cell parameter is updated to the current cell parameter; if no, the second cell parameter is not updated. The following describes the dynamic thermal management method for energy storage cells provided in this application embodiment with a specific example.

[0070] During the operation of the energy storage BMS, the dynamic thermal management algorithm executes the following dynamic thermal management process for energy storage cells to control the target cooling temperature, including the following steps: Step 1: After the energy storage BMS is powered on, execute the initialization process.

[0071] The main initialization steps are as follows: ① Set the timer count variables for 1-minute step control and 5-minute step control to 0; ② Initialize the initial value of the cooling target temperature; ③ Obtain the first maximum cell temperature value and the first average cell temperature value controlled by the 1-minute step control; ④ Obtain the second maximum cell temperature value and the second average cell temperature value controlled by the 5-minute step control. In this embodiment, an example is provided with a first preset time step of 1 minute and a second preset time step of 5 minutes.

[0072] Step 2: Determine if the water purifier is in cooling mode. If it is in cooling mode, then implement dynamic control; otherwise, exit the cooling target temperature control mode.

[0073] Step 3: Calculate the first maximum cell temperature difference and the first average cell temperature difference in the 1-minute step size control.

[0074] Step 4: In the 1-minute step size control, determine whether the first maximum cell temperature difference or the first average cell temperature difference is greater than +0.2℃. If it is greater than +0.2℃, the change in the cooling target temperature is -1; otherwise, determine whether the first maximum cell temperature difference or the first average cell temperature difference is less than -0.3℃. If it is less than -0.3℃, the change in the cooling target temperature is +1.

[0075] Step 5: If the control condition of 1min control step size is not met, it is necessary to calculate the second maximum cell temperature difference and the second average cell temperature difference under 5min step size control.

[0076] Step 6: Based on the second maximum cell temperature value and the second maximum cell temperature difference in the 5-minute control step, look up the table to obtain the temperature change amount 1, which is the first temperature change amount.

[0077] Step 7: Based on the second average cell temperature value and the second average cell temperature difference in the 5-minute control step, look up the table to obtain the temperature change amount 2, i.e., the second temperature change amount.

[0078] Step 8: Take the smaller of temperature change 1 and temperature change 2 as the final determined target temperature change for cooling.

[0079] Step 9: Determine if the change in the final target cooling temperature is 0. If the change in the target cooling temperature is 0, it is considered that the current target cooling temperature does not need to be adjusted. If the change in the target cooling temperature is not 0, it is considered that the current target cooling temperature needs to be adjusted. Simultaneously, clear the timer count variable values ​​under the 1-minute and 5-minute control steps, update the first average cell temperature value and the first maximum cell temperature value under the 1-minute control step, and update the second average cell temperature value and the second maximum cell temperature value under the 5-minute control step.

[0080] Step 10: Accumulate the change in the target cooling temperature based on the initial value of the previous target cooling temperature, and limit the accumulated target cooling temperature value.

[0081] If the change in the target cooling temperature is 0, then steps 11 and 12 need to be executed.

[0082] Step 11: Determine whether the timer for the 1-minute control step has reached the 1-minute cycle. If it has, update the first average cell temperature value and the first maximum cell temperature value under the 1-minute control step to the average cell temperature value and the maximum cell temperature value at the current moment.

[0083] Step 12: Determine whether the timer for the 5-minute control step has reached the 5-minute cycle. If it has, update the second average cell temperature value and the second maximum cell temperature value under the 5-minute control step to the average cell temperature value and the maximum cell temperature value at the current moment.

[0084] Steps 2-12 constitute a process for dynamic thermal management of the energy storage cells. During the operation of the energy storage system, steps 2-12 are repeated to perform dynamic thermal management of the energy storage cells.

[0085] The dynamic thermal management method for energy storage cells provided in this specific embodiment has several advantages. First, it maintains the cell temperature within a safe and efficient optimal temperature range during system operation by controlling the temperature range of the cell during operation through temperature control equipment such as liquid chillers. Second, by employing a variable step size method to control the target cooling temperature, this method ensures the control algorithm's response speed to changes in cell temperature, improving the accuracy of cell temperature control. Third, this method not only selects the maximum and average cell temperature values ​​as input variables but also uses the changes in these values ​​as input variables, considering cell temperature changes from multiple dimensions to make the changes in the target cooling temperature more reasonable. Fourth, by controlling the maximum... The control of the cell temperature difference and the average cell temperature difference adopts a control step size of less than 1 minute, which makes the control algorithm more sensitive to the changes in cell temperature in a short period of time. In the face of the situation where the cell temperature rises rapidly due to the charging and discharging current, the liquid cooling unit can take action in advance to control and intervene. By adopting a control step size of 5 minutes for the control of the maximum cell temperature value, the maximum cell temperature difference, the average cell temperature value, and the average cell temperature difference, the control algorithm can be more sensitive to the temperature level and the trend of the cell temperature within 5 minutes. In the face of the situation where the cell temperature rises slowly and continuously over a period of time due to the small current charging and discharging, the liquid cooling unit can be controlled and intervened in a timely manner.

[0086] Figure 4 The structural block diagram of a dynamic thermal management device for energy storage cells is shown in the embodiment of this application.

[0087] The dynamic thermal management device for energy storage cells provided in this application includes the following functional modules: Calculation module 401 is used to calculate the first cell temperature difference parameter according to the first cell parameters corresponding to the first preset time step managed in the system after the energy storage system is initialized. The first cell parameters include: a first maximum cell temperature value and a first average cell temperature value; the first cell temperature difference parameter includes: a first maximum cell temperature difference and a first average cell temperature difference. The first determining module 402 is used to determine the target temperature change of cooling according to the first cell temperature difference parameter when it is determined that the water turbine in the energy storage system is in a cooling state. The second determining module 403 is used to determine the change in cooling target temperature according to the second cell parameter corresponding to the second preset time step managed in the system and the current cell parameter collected when the first cell temperature difference parameter does not meet the preset control conditions. The adjustment module 404 is used to adjust the cooling target temperature according to the change in the cooling target temperature, so as to adjust the temperature of the energy storage cell.

[0088] Optionally, the device further includes an initialization module for: Determine whether the initialization flag of the energy storage system indicates that initialization has been completed; If not, initiate the energy storage system initialization process and set the timing variable to 0; Set the initial value of the target cooling temperature to the preset temperature value; Obtain the parameters of the first battery cell corresponding to the first preset time step managed in the system; Obtain the second cell parameters corresponding to the second preset time step managed in the system to complete the energy storage system initialization.

[0089] Optionally, the first determining module is specifically used for: If it is determined that the water turbine in the energy storage system is in a cooling state, it is determined whether at least one of the first maximum cell temperature difference and the first average cell temperature difference is greater than a first value; if so, the target cooling temperature change is determined to be a decrease of a second value. If not, determine whether at least one of the first maximum cell temperature difference and the first average cell temperature difference is less than the third value; if yes, determine that the change in the cooling target temperature is to increase the second value; wherein, the first value is a positive number and the third value is a negative number; if not, determine that the preset control conditions are not met.

[0090] Optionally, the second determining module includes: The first submodule is used to calculate the second cell temperature difference parameter according to the second cell parameters corresponding to the second preset time step and the collected current cell parameters, wherein the second cell temperature difference parameter includes: the second maximum cell temperature difference and the second average cell temperature difference; the second cell parameters include: the second maximum cell temperature value and the second average cell temperature value; The second submodule is used to determine the first temperature change corresponding to the second maximum cell temperature value based on the second maximum cell temperature value and the second maximum cell temperature difference. The third submodule is used to determine the second temperature change corresponding to the second average cell temperature value based on the second average cell temperature value and the second average cell temperature difference. The fourth submodule is used to take the minimum value between the first temperature change and the second temperature change as the target temperature change for cooling.

[0091] Optionally, the third submodule is specifically used for: Determine whether the second average cell temperature value is lower than the average temperature value when cooling is turned on; If not, determine the first temperature range to which the second average cell temperature value belongs, and determine the corresponding column value in the first preset table based on the first temperature range; Determine the first temperature difference range to which the second average cell temperature difference belongs, and determine the corresponding row value in the first preset table based on the first temperature difference range; Based on the row value and the column value, find the second temperature change corresponding to the second average cell temperature value in the first preset table.

[0092] Optionally, the second submodule is specifically used for: Determine whether the second maximum cell temperature value is less than the maximum temperature value when the cooling is turned on; If not, determine the second temperature range to which the second maximum cell temperature value belongs, and determine the corresponding column value in the second preset table based on the second temperature range; Determine the second temperature difference range to which the second maximum cell temperature difference belongs, and determine the corresponding row value in the second preset table based on the second temperature difference range; Based on the row value and the column value, find the first temperature change corresponding to the second maximum cell temperature value in the second preset table.

[0093] Optionally, the device further includes an update module for: Determine whether the change in the target cooling temperature is 0; If the change in the target cooling temperature is not 0, then the first cell parameter corresponding to the first preset time step managed in the system is updated to the current cell parameter, and the second cell parameter corresponding to the second preset time step is updated to the current cell parameter. If the change in the target cooling temperature is 0, then determine whether the time since the first cell parameter was not updated has reached the first preset time step; if yes, then update the first cell parameter to the current cell parameter; if no, then do not update the first cell parameter. If the change in the target cooling temperature is 0, then determine whether the time since the second cell parameter was not updated has reached the second preset time step; if yes, then update the second cell parameter to the current cell parameter; if no, then do not update the second cell parameter.

[0094] The embodiments provided in this application Figure 4 The dynamic thermal management device for the energy storage cells shown can achieve Figure 1 The various processes implemented in the method implementation examples will not be described again here to avoid repetition.

[0095] This invention also provides an electronic device, including a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus.

[0096] Memory, used to store computer programs; When the processor executes the program stored in the memory, it implements the dynamic thermal management method for energy storage cells shown in the above method embodiments.

[0097] The communication bus mentioned above can be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. This communication bus can be divided into address bus, data bus, control bus, etc.

[0098] The communication interface is used for communication between the aforementioned terminal and other devices.

[0099] The memory may include random access memory (RAM) or non-volatile memory, such as at least one disk storage device. Optionally, the memory may also be at least one storage device located remotely from the aforementioned processor.

[0100] In another embodiment of the present invention, a computer-readable storage medium is also provided, which stores instructions that, when executed on an electronic device, cause the electronic device to implement the dynamic thermal management method for energy storage cells described in any of the above embodiments.

[0101] In another embodiment of the present invention, a computer program product containing instructions is also provided, which, when run on an electronic device, enables the electronic device to implement the dynamic thermal management method for energy storage cells described in any of the above embodiments.

[0102] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0103] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A dynamic thermal management method for energy storage cells, characterized in that, The method includes: After the energy storage system is initialized, the first cell temperature difference parameter is calculated according to the first cell parameters corresponding to the first preset time step managed in the system and the current cell parameters collected. The first cell parameters include: the first maximum cell temperature value and the first average cell temperature value; the first cell temperature difference parameter includes: the first maximum cell temperature difference and the first average cell temperature difference. When it is determined that the water turbine in the energy storage system is in a cooling state, the target temperature change is determined according to the first cell temperature difference parameter. If the temperature difference parameter of the first cell does not meet the preset control conditions, the change in the target cooling temperature is determined according to the second cell parameter corresponding to the second preset time step managed in the system and the current cell parameter collected. The target cooling temperature is adjusted based on the change in the target cooling temperature to adjust the temperature of the energy storage cell.

2. The method according to claim 1, characterized in that, Before the step of calculating the first cell temperature difference parameter according to the first cell parameter corresponding to the first preset time step managed in the system and the collected current cell parameter after the energy storage system initialization is completed, the method further includes: Determine whether the initialization flag of the energy storage system indicates that initialization has been completed; If not, initiate the energy storage system initialization process and set the timing variable to 0; Set the initial value of the target cooling temperature to the preset temperature value; Obtain the parameters of the first battery cell corresponding to the first preset time step managed in the system; Obtain the second cell parameters corresponding to the second preset time step managed in the system.

3. The method according to claim 1, characterized in that, The step of determining the target temperature change based on the first cell temperature difference parameter when the water turbine in the energy storage system is determined to be in a cooling state includes: If it is determined that the water turbine in the energy storage system is in a cooling state, it is determined whether at least one of the first maximum cell temperature difference and the first average cell temperature difference is greater than a first value; if so, the target cooling temperature change is determined to be a decrease of a second value. If not, determine whether at least one of the first maximum cell temperature difference and the first average cell temperature difference is less than the third value; if yes, determine that the change in the cooling target temperature is to increase the second value; wherein, the first value is a positive number and the third value is a negative number; if not, determine that the preset control conditions are not met.

4. The method according to claim 1, characterized in that, The steps for determining the change in the target cooling temperature based on the second cell parameters corresponding to the second preset time step and the collected current cell parameters include: The second cell temperature difference parameter is calculated based on the second cell parameters corresponding to the second preset time step and the collected current cell parameters. The second cell temperature difference parameter includes: the second maximum cell temperature difference and the second average cell temperature difference; the second cell parameters include: the second maximum cell temperature value and the second average cell temperature value. Based on the second maximum cell temperature value and the second maximum cell temperature difference, determine the first temperature change corresponding to the second maximum cell temperature value; Based on the second average cell temperature value and the second average cell temperature difference, determine the second temperature change corresponding to the second average cell temperature value; The minimum of the first temperature change and the second temperature change is taken as the target temperature change for cooling.

5. The method according to claim 4, characterized in that, The step of determining the second temperature change corresponding to the second average cell temperature value based on the second average cell temperature value and the second average cell temperature difference includes: Determine whether the second average cell temperature value is lower than the average temperature value when cooling is turned on; If not, determine the first temperature range to which the second average cell temperature value belongs, and determine the corresponding column value in the first preset table based on the first temperature range; Determine the first temperature difference range to which the second average cell temperature difference belongs, and determine the corresponding row value in the first preset table based on the first temperature difference range; Based on the row value and the column value, find the second temperature change corresponding to the second average cell temperature value in the first preset table.

6. The method according to claim 4, characterized in that, The step of determining the first temperature change corresponding to the second maximum cell temperature value based on the second maximum cell temperature value and the second maximum cell temperature difference includes: Determine whether the second maximum cell temperature value is less than the maximum temperature value when the cooling is turned on; If not, determine the second temperature range to which the second maximum cell temperature value belongs, and determine the corresponding column value in the second preset table based on the second temperature range; Determine the second temperature difference range to which the second maximum cell temperature difference belongs, and determine the corresponding row value in the second preset table based on the second temperature difference range; Based on the row value and the column value, find the first temperature change corresponding to the second maximum cell temperature value in the second preset table.

7. The method according to claim 1, characterized in that, The method further includes: Determine whether the change in the target cooling temperature is 0; If the change in the target cooling temperature is not 0, then the first cell parameter corresponding to the first preset time step managed in the system is updated to the current cell parameter, and the second cell parameter corresponding to the second preset time step is updated to the current cell parameter. If the change in the target cooling temperature is 0, then determine whether the time since the first cell parameter was not updated has reached the first preset time step; if yes, then update the first cell parameter to the current cell parameter; if no, then do not update the first cell parameter. If the change in the target cooling temperature is 0, then determine whether the time since the second cell parameter was not updated has reached the second preset time step; if yes, then update the second cell parameter to the current cell parameter; if no, then do not update the second cell parameter.

8. A dynamic thermal management device for energy storage cells, characterized in that, The device includes: The calculation module is used to calculate the first cell temperature difference parameter after the energy storage system is initialized, according to the first cell parameters corresponding to the first preset time step managed in the system and the collected current cell parameters. The first cell parameters include: a first maximum cell temperature value and a first average cell temperature value; the first cell temperature difference parameter includes: a first maximum cell temperature difference and a first average cell temperature difference. The first determining module is used to determine the target temperature change of cooling according to the first cell temperature difference parameter when it is determined that the water turbine in the energy storage system is in a cooling state. The second determining module is used to determine the change in cooling target temperature according to the second cell parameter corresponding to the second preset time step managed in the system and the collected current cell parameter when the first cell temperature difference parameter does not meet the preset control conditions. The adjustment module is used to adjust the cooling target temperature according to the change in the cooling target temperature, so as to adjust the temperature of the energy storage cell.

9. The apparatus according to claim 8, characterized in that, The device further includes an initialization module for: Determine whether the initialization flag of the energy storage system indicates that initialization has been completed; If not, initiate the energy storage system initialization process and set the timing variable to 0; Set the initial value of the target cooling temperature to the preset temperature value; Obtain the parameters of the first battery cell corresponding to the first preset time step managed in the system; Obtain the second cell parameters corresponding to the second preset time step managed in the system to complete the energy storage system initialization.

10. An electronic device, characterized in that, It includes a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus; Memory, used to store computer programs; The processor, when executing a program stored in the memory, implements the dynamic thermal management method for energy storage cells as described in any one of claims 1-7.

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