Temperature control system for energy storage systems and method thereof

Abstract

The application provides a temperature control system for an energy storage system and a method thereof, which comprises a water chiller, a plurality of parallel battery clusters and a controller. Each battery cluster comprises at least one battery pack, and each battery pack is provided with an independent temperature sensor. The system adopts three-stage liquid cooling pipelines, i.e., a first-stage pipeline connected with the water chiller, a second-stage pipeline corresponding to the battery clusters and a third-stage pipeline corresponding to the battery packs. The key point is that a flow regulating unit is arranged at the connection between the second-stage return water pipeline of each battery cluster and the first-stage return water pipeline. The controller independently adjusts the opening degree of the corresponding flow regulating unit according to the data of the temperature sensors and controls the outlet water temperature of the water chiller. The system can independently adjust the opening degree of the flow regulating unit and then regulate the flow of the cooling medium flowing to each battery cluster, so that the temperature difference between different battery clusters can be effectively eliminated and local overheating can be prevented. Therefore, the temperature uniformity, operation safety and battery service life of the energy storage system are significantly improved.

Description

Technical Field

[0001] This invention relates to the field of thermal management technology for energy storage systems, and more specifically, to a temperature control system and method for energy storage systems. Background Technology

[0002] With the rapid growth of installed capacity and the continuous expansion of single-unit scale of electrochemical energy storage power stations, thermal management of energy storage batteries has become a core aspect concerning system operation safety, lifespan, and overall performance. Currently, containerized energy storage systems generally use chillers for cooling, and their mainstream control strategy still follows the traditional industrial refrigeration mode, that is, monitoring the average temperature of the entire battery pack cooling circuit through a single temperature sensor, and using this feedback signal to start / stop the compressor or adjust its frequency.

[0003] However, this crude temperature control method based on average temperature has fundamental flaws when dealing with the complex thermal distribution characteristics inside the battery pack. Although thermal simulation and fluid distribution calculations may have been performed during the piping design phase, significant temperature differences exist between different battery clusters during the actual operation of the energy storage system. This inconsistency not only affects the overall lifespan of the battery pack, but more seriously, localized overheating points are a key hidden danger that can induce a chain reaction of thermal runaway, posing a continuous threat to the safety of the energy storage system. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a temperature control system and method for an energy storage system, addressing the aforementioned technical deficiencies in the prior art. The temperature control system includes a chiller unit and multiple battery clusters connected in parallel, each battery cluster including at least one battery pack. It also includes a primary liquid cooling supply pipe and a primary liquid cooling return pipe connected to the chiller unit, a secondary liquid cooling supply pipe and a secondary liquid cooling return pipe corresponding to each battery cluster, and a tertiary liquid cooling supply pipe and a tertiary liquid cooling return pipe corresponding to each battery pack; it also includes: multiple temperature sensors, one for each battery pack, for collecting temperature data of the corresponding battery pack; multiple flow regulation units, each flow regulation unit being located at the connection between the secondary liquid cooling return pipe and the primary liquid cooling return pipe of the corresponding battery cluster, for regulating the flow rate of the cooling medium to the corresponding battery cluster; a controller, communicatively connected to the multiple temperature sensors and electrically connected to the chiller unit and the multiple flow regulation units; the controller is used to control the opening degree of the flow regulation units and the outlet water temperature of the chiller unit according to the temperature data.

[0005] Furthermore, the flow regulating unit is a three-way mixing valve, which has a first inlet, a second inlet, and an outlet. The first inlet is connected to the upstream section of the primary liquid cooling pipeline return water pipe, the second inlet is connected to the secondary liquid cooling pipeline return water pipe corresponding to the battery cluster, and the outlet is connected to the downstream section of the primary liquid cooling pipeline return water pipe.

[0006] Furthermore, the chiller unit includes a circulating water pump, which drives the cooling medium to flow in the primary liquid cooling pipeline supply pipe and the primary liquid cooling pipeline return pipe, the secondary liquid cooling pipeline supply pipe, the secondary liquid cooling pipeline return pipe, the tertiary liquid cooling pipeline supply pipe, and the tertiary liquid cooling pipeline return pipe.

[0007] Furthermore, the inlet end of the secondary liquid cooling pipeline water supply pipe is connected to the primary liquid cooling pipeline water supply pipe, and the outlet end of the secondary liquid cooling pipeline water supply pipe is connected to the inlet end of the tertiary liquid cooling pipeline water supply pipe.

[0008] The present invention also provides a temperature control method for an energy storage system, applied to the temperature control system described in any of the above claims, comprising the following steps: Step S1: Collect temperature data of each battery pack using the multiple temperature sensors; Step S2: Based on the temperature data, control the opening degree of the flow regulation unit and the outlet water temperature of the chiller unit to independently regulate the flow rate and temperature of the cooling medium flowing to each battery cluster.

[0009] Further, step S2 includes: The representative temperature Ti of each battery cluster is obtained based on the temperature data. Based on the representative temperature Ti, calculate the temperature deviation ΔTdevi of each battery cluster and the maximum temperature difference ΔTmax between clusters; Based on the temperature deviation △Tdevi, calculate the temperature setting compensation value △Tseti for each battery cluster; Based on the maximum temperature difference between clusters △Tmax and the representative temperature Ti of each battery cluster, the opening compensation value △Ki is calculated for the flow regulation unit corresponding to each battery cluster. The outlet water temperature of the chiller unit is adjusted according to the temperature setting compensation value △Tseti. The opening degree of the flow regulation unit of the corresponding battery cluster is adjusted according to the opening degree compensation value △Ki.

[0010] Furthermore, the representative temperature Ti is the highest temperature of all cells in the corresponding battery cluster.

[0011] Further, the temperature deviation ΔTdevi = Ti - Tavg, where Tavg is the average value of the representative temperatures of all battery clusters; the maximum temperature difference between clusters ΔTmax = max(Ti) - min(Ti), where max(Ti) is the maximum value among the representative temperatures of all battery clusters, and min(Ti) is the minimum value among the representative temperatures of all battery clusters.

[0012] Furthermore, the temperature set compensation value ΔTseti is calculated using the following formula: △Tseti=-Kp×△Tdevi-Kd×(△Tdevi-△Tdevi_pre); Where Kp and Kd are control coefficients, and △Tdevi_pre is the temperature deviation of the previous cycle.

[0013] Furthermore, the opening compensation value △Ki is calculated through the following steps: Calculate the heat demand Hi for each battery cluster, where Hi = (Ti - min(Ti)) / ΔTmax; The opening compensation value △Ki is calculated based on the heat demand Hi, where △Ki = α × Hi, α is the temperature difference adjustment coefficient, and its sign and magnitude are determined by the maximum temperature difference between clusters △Tmax.

[0014] The beneficial effects of this invention are that it provides a temperature control system and method for an energy storage system. The temperature control system includes a chiller unit, multiple battery clusters arranged in parallel, each battery cluster including at least one battery pack; it also includes a primary liquid cooling pipeline supply pipe and a primary liquid cooling pipeline return pipe connected to the chiller unit, a secondary liquid cooling pipeline supply pipe and a secondary liquid cooling pipeline return pipe corresponding to each battery cluster, and a tertiary liquid cooling pipeline supply pipe and a tertiary liquid cooling pipeline return pipe corresponding to each battery pack; it further includes: multiple temperature sensors, one for each battery pack, for collecting temperature data of the corresponding battery pack; multiple flow regulation units, each flow regulation unit being located at the connection between the secondary liquid cooling pipeline return pipe and the primary liquid cooling pipeline return pipe of the corresponding battery cluster, for regulating the flow rate of cooling medium to the corresponding battery cluster; and a controller, communicatively connected to the multiple temperature sensors and electrically connected to the chiller unit and the multiple flow regulation units; the controller is used to control the opening degree of the flow regulation units and the outlet water temperature of the chiller unit according to the temperature data. This invention achieves independent regulation of the cooling medium flow rate for each battery cluster and coordinated control of the chiller outlet water temperature by setting a flow regulation unit at the connection between the secondary liquid cooling pipeline return pipe and the primary liquid cooling pipeline return pipe of each battery cluster, combined with an independently set temperature sensor and controller for each battery pack. This effectively eliminates temperature differences between different battery clusters, avoids the generation of local overheating spots, and significantly improves the temperature uniformity, operational safety, and battery life of the energy storage system. Attached Figure Description

[0015] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings: Figure 1 This is a schematic diagram of the temperature control system of the present invention used in an energy storage system; Figure 2 This is a schematic flowchart of the temperature control method for energy storage systems in this invention; Figure 3 This is a flowchart illustrating the method for calculating the temperature setting compensation value according to the present invention. Detailed Implementation

[0016] To provide a clearer understanding of the technical features, objectives, and effects of the present invention, specific embodiments of the invention are now described in detail with reference to the accompanying drawings. In the following description, specific details such as particular structures and techniques are set forth for illustrative purposes and not for limitation, so as to provide a thorough understanding of the embodiments of the invention. However, those skilled in the art will understand that the invention can also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known devices, circuits, and methods are omitted so as not to obscure the description of the invention with unnecessary detail.

[0017] To address the technical problems of large temperature differences between different battery clusters and potential localized overheating caused by average temperature control in existing energy storage systems, this invention provides a temperature control system for energy storage systems. By installing a flow regulation unit at the connection between the secondary liquid cooling pipeline return pipe and the primary liquid cooling pipeline return pipe of each battery cluster, and combining this with an independently installed temperature sensor and controller for each battery pack, the system achieves independent regulation of the cooling medium flow rate for each battery cluster and coordinated control of the chiller outlet water temperature. This effectively eliminates temperature differences between different battery clusters, avoids the generation of localized overheating spots, and significantly improves the temperature uniformity, operational safety, and battery life of the energy storage system.

[0018] like Figure 1 As shown, Figure 1 This is a connection diagram of a temperature control system used in an energy storage system.

[0019] In a preferred embodiment, the temperature control system includes a chiller unit 1 and a plurality of battery clusters arranged in parallel, each battery cluster including at least one battery pack 9; It also includes a primary liquid cooling water supply pipe 2 and a primary liquid cooling water return pipe 3 connected to the chiller unit 1; a secondary liquid cooling water supply pipe 5 and a secondary liquid cooling water return pipe 6 corresponding to each battery cluster; and a tertiary liquid cooling water supply pipe 7 and a tertiary liquid cooling water return pipe 8 corresponding to each battery pack 9; it also includes: multiple temperature sensors, one for each battery pack 9, used to collect the temperature of the corresponding battery pack; multiple flow regulation units, each flow regulation unit is located at the connection between the secondary liquid cooling water return pipe 6 and the primary liquid cooling water return pipe 3 of the corresponding battery cluster, used to regulate the flow rate of the cooling medium to the corresponding battery cluster; a controller, which is communicatively connected to the multiple temperature sensors and electrically connected to the chiller unit 1 and the multiple flow regulation units; the controller is used to control the opening degree of the flow regulation units and the outlet water temperature of the chiller unit according to the temperature data collected by the temperature sensors.

[0020] Specifically, this invention constructs a high-resolution temperature sensing network by setting independent temperature sensors in each battery pack. These sensors can be NTC thermistors or thermocouples attached to the surface of the battery cells or integrated into the module, enabling real-time and accurate capture of the microscopic thermal state of each battery pack. More importantly, a flow regulation unit is set at the node where the return water from each battery cluster flows into the primary return water pipe, giving the controller an "actuator" for independent thermal intervention of each battery cluster. The controller collects data from all temperature sensors in real time via a high-speed communication bus (such as CAN or RS485), processes the data, and simultaneously sends an outlet water temperature regulation command to chiller unit 1 and an opening degree regulation command to each flow regulation unit. This closed-loop control link of "sensing-decision-execution" provides a fundamental technical guarantee for eliminating inter-cluster temperature differences and suppressing local overheating.

[0021] Furthermore, the flow regulation unit is a three-way mixing valve 4, which has a first inlet, a second inlet and an outlet. The first inlet is connected to the upstream section of the primary liquid cooling pipeline return water pipe 3, the second inlet is connected to the secondary liquid cooling pipeline return water pipe 6 corresponding to the battery cluster, and the outlet is connected to the downstream section of the primary liquid cooling pipeline return water pipe 3.

[0022] Specifically, a three-way mixing valve 4 is selected as the flow regulation unit. The working principle of the three-way mixing valve 4 is as follows: the first inlet receives low-temperature return water (upstream section) from other battery clusters and cooled by the chiller unit 1; the second inlet receives high-temperature return water discharged from the current battery cluster itself. The controller controls the mixing ratio of these two different temperature water flows within the valve body by adjusting the valve core opening ratio. For example, when the temperature of a battery cluster is too high and requires enhanced cooling, the controller increases the opening of the first inlet (low-temperature water) while decreasing the opening of the second inlet (high-temperature water), resulting in a lower temperature of the water flowing out after mixing. Simultaneously, the overall return water resistance flowing through that battery cluster decreases, and the flow rate increases. Conversely, if the temperature of a battery cluster is too low, the proportion of low-temperature water can be reduced and the proportion of high-temperature water increased to appropriately raise the temperature of its cooling medium and avoid over-cooling. This mixing and regulating mechanism has two major advantages: First, it enables independent fine-tuning of the temperature of the cooling medium entering each battery cluster without changing the overall outlet water temperature of chiller unit 1, resulting in extremely fast response. Second, it utilizes the energy already present in the return water pipeline, regulating temperature through mixing, which is more energy efficient than direct heating or additional cooling. Therefore, the introduction of the three-way mixing valve 4 allows the system to maintain stable operation of chiller unit 1 while providing a precise and energy-efficient response to localized heat load changes.

[0023] Furthermore, the chiller unit 1 includes a circulating water pump, which drives the cooling medium to circulate in the primary liquid cooling pipeline, the secondary liquid cooling pipeline and the tertiary liquid cooling pipeline.

[0024] The circulating water pump is used to drive the cooling medium to flow in the primary liquid cooling pipeline supply pipe 2 and the primary liquid cooling pipeline return pipe 3, the secondary liquid cooling pipeline supply pipe 5, the secondary liquid cooling pipeline return pipe 6, the tertiary liquid cooling pipeline supply pipe 7, and the tertiary liquid cooling pipeline return pipe 8.

[0025] Specifically, the circulating water pump provides continuous power for the circulation of the cooling medium. Driven by the circulating water pump, the cooling medium (usually an aqueous solution of ethylene glycol) flows out from the outlet of the chiller unit 1, through the primary liquid cooling pipeline supply pipe 2, and then splits into the parallel secondary liquid cooling pipeline supply pipes 5, and further splits into the tertiary liquid cooling pipeline supply pipes 7 of each battery pack 9. While flowing through the liquid cooling plates inside the battery pack 9, the cooling medium absorbs the heat generated during battery charging and discharging, causing its temperature to rise. The heated cooling medium then flows through the tertiary liquid cooling pipeline return pipe 8 to the secondary liquid cooling pipeline return pipe 6, and finally through the three-way mixing valve 4 back into the primary return pipe 3, flowing back to the chiller unit 1. Inside the chiller unit 1, the high-temperature cooling medium transfers heat to the refrigeration system through a heat exchanger, lowering its own temperature, and is then pressurized and sent out by the circulating water pump to begin a new cycle. The selection of the circulating water pump (such as head and flow rate) is matched with the resistance characteristics of the entire piping system to ensure that even under the most unfavorable operating conditions, the furthest battery pack 9 can obtain sufficient cooling flow. In addition, the application of variable frequency circulating water pumps can further optimize system energy efficiency by reducing the speed when the heat load is low, thereby reducing unnecessary energy consumption.

[0026] Furthermore, the inlet end of the secondary liquid cooling pipeline water supply pipe 5 is connected to the primary liquid cooling pipeline water supply pipe 2, and the outlet end of the secondary liquid cooling pipeline water supply pipe 5 is connected to the inlet end of the tertiary liquid cooling pipeline water supply pipe 7.

[0027] like Figure 2 As shown, the invention also provides a temperature control method for an energy storage system, applied to the temperature control system of any of the above, comprising the following steps: Step S1: collecting temperature data of each battery pack through multiple temperature sensors; Step S2: controlling the opening degree of the flow regulation unit and the outlet water temperature of the chiller unit 1 according to the temperature data, so as to independently regulate the flow rate and temperature of the cooling medium flowing to each battery cluster.

[0028] The controller is the primary implementer of this temperature control method. In step S1, the controller polls or reads data from all temperature sensors in parallel via a communication bus (such as CAN bus, RS485 bus, or Ethernet) at a fixed sampling period (e.g., 1 second, 5 seconds, or 10 seconds, which can be set according to the system's dynamic response requirements). These temperature sensors are preferably NTC thermistors or thermocouples attached to the surface of the cells inside the battery pack 9 or integrated inside the battery module, featuring high accuracy and fast response. The collected temperature data is stored in real time in the controller's data register, forming a multi-dimensional temperature matrix describing the thermal state of the entire energy storage system. This matrix includes timestamps, battery cluster numbers, battery pack numbers, and corresponding temperature values, providing a rich and detailed data foundation for subsequent control decisions. In step S2, the controller's built-in collaborative control algorithm performs in-depth processing on the temperature matrix collected in step S1. The core idea of ​​this algorithm is to decouple the temperature control task into two independent yet coordinated layers: first, the regulation of the global temperature level, achieved by changing the outlet water temperature of chiller unit 1, which determines the system's basic cooling capacity, has a relatively slow response but affects the overall system; second, the regulation of local temperature difference balance, achieved by independently changing the opening degree of each flow regulation unit, which determines the local cooling distribution of each battery cluster, has a fast response speed, and can accurately suppress hot spots. The controller generates two sets of parallel control commands through real-time calculations: one set is sent to the controller of chiller unit 1 (usually via industrial protocols such as Modbus) to adjust its outlet water temperature setpoint; the other set is sent to the actuators of each flow regulation unit (such as the motor of the electric three-way mixing valve) to adjust its valve opening. This dual-layer coordinated control strategy of temperature and flow regulation ensures that the system can follow changes in the total heat load while actively eliminating uneven internal heat distribution, representing an innovative solution to the temperature control problem of energy storage systems. In one embodiment, a valve may be installed on the secondary liquid cooling pipeline water supply pipe 5 of each battery cluster at the part connected to the primary liquid cooling pipeline water supply pipe 2, so that the temperature of each battery cluster can be adjusted individually.

[0029] Further, step S2 includes: obtaining the representative temperature Ti of each battery cluster based on temperature data; calculating the temperature deviation ΔTdevi and the maximum temperature difference ΔTmax between each battery cluster based on the representative temperature Ti; calculating the temperature setting compensation value ΔTseti for each battery cluster based on the temperature deviation ΔTdevi; calculating the opening compensation value ΔKi for the flow regulation unit corresponding to each battery cluster based on the maximum temperature difference ΔTmax between clusters and the representative temperature Ti of each battery cluster; adjusting the outlet water temperature of the chiller unit 1 based on the temperature setting compensation value ΔTseti; and adjusting the opening degree of the flow regulation unit of the corresponding battery cluster based on the opening compensation value ΔKi.

[0030] Furthermore, the representative temperature Ti is the highest temperature of all cells in the corresponding battery cluster.

[0031] Furthermore, the temperature deviation ΔTdevi = Ti - Tavg, where Tavg is the average of the representative temperatures of all battery clusters; the maximum temperature difference between clusters ΔTmax = max(Ti) - min(Ti), where max(Ti) is the maximum value among the representative temperatures of all battery clusters, and min(Ti) is the minimum value among the representative temperatures of all battery clusters.

[0032] Specifically, when Ti of a cluster is higher than Tavg, ΔTdevi is positive, indicating that the cluster is a "hot zone" in the system and needs more cooling resources; when Ti is lower than Tavg, ΔTdevi is negative, indicating that the cluster is a "cold zone" and the allocation of cooling resources can be appropriately reduced. This relative coordinate not only quantifies the priority of cooling requirements for each cluster, but also provides a direct input variable for the subsequent PD controller. The calculation of the maximum temperature difference between clusters, ΔTmax, provides another dimension of system state information—temperature uniformity. ΔTmax directly measures the extreme difference between hot and cold zones in the system and is a comprehensive health indicator. When ΔTmax is maintained within a small range (e.g., ≤3°C), it indicates that the system has a uniform heat distribution and good battery consistency; when ΔTmax gradually increases and exceeds a preset threshold (e.g., 5°C), it is a clear warning signal, indicating that the system has significant thermal imbalance, which may be due to increased internal resistance of some batteries, loose connections, or blocked cooling channels, requiring immediate activation of the equalization control strategy. The magnitude of ΔTmax directly determines the intensity of subsequent flow regulation; the greater the temperature difference, the stronger the regulation.

[0033] like Figure 3 As shown, the temperature setpoint compensation value ΔTseti is further calculated using the following formula: △Tseti=-Kp×△Tdevi-Kd×(△Tdevi-△Tdevi_pre); Where Kp and Kd are control coefficients, and △Tdevi_pre is the temperature deviation of the previous cycle.

[0034] Specifically, the presence of the negative sign in the above formula ensures the negative feedback characteristic of the control: when ΔTdevi is positive (cluster temperature is too high), ΔTseti is negative, indicating a decrease in outlet water temperature; conversely, it increases the outlet water temperature, forming the correct adjustment direction. The proportional term Kp × ΔTdevi is responsible for making an immediate response to the current temperature deviation, and its coefficient Kp determines the sensitivity of the response. In engineering practice, the tuning of Kp needs to comprehensively consider the cooling capacity of the chiller unit and the thermal inertia of the system. If Kp is too small, the system response is slow and it is difficult to quickly suppress the temperature rise; if Kp is too large, it may lead to frequent fluctuations in outlet water temperature, or even cause system oscillation. The differential term Kd × (ΔTdevi - ΔTdevi_pre) reflects the predictive ability of the algorithm, where (ΔTdevi - ΔTdevi_pre) is the change in temperature deviation in the current cycle, reflecting the trend of the deviation. When the deviation is accelerating (e.g., a cluster rapidly heats up due to a sudden increase in charging / discharging power), the derivative term generates an additional adjustment to preemptively increase the cooling rate, acting as a preventative measure. When the deviation is converging, the derivative term appropriately weakens the adjustment to avoid excessive backlash. This synergistic effect of "proportional adjustment for current correction and derivative adjustment for advanced prediction" allows the chiller unit's outlet water temperature to adapt smoothly and quickly to dynamic changes in system heat load. To ensure system stability, ΔTseti is set with upper and lower limits (e.g., ±3℃) to prevent excessive deviation from the setpoint from causing system oscillation. Ultimately, the actual outlet water temperature setpoint for each battery cluster is: Tset_i = Tset + ΔTseti, where Tset is the chiller unit's base outlet water temperature setpoint, which can be the factory default value or determined by the average temperature of all cells.

[0035] Furthermore, the opening compensation value △Ki is calculated through the following steps: calculate the heat demand Hi of each battery cluster, where Hi=(Ti-min(Ti)) / △Tmax; calculate the opening compensation value △Ki based on the heat demand Hi, where △Ki=α×Hi, α is the temperature difference adjustment coefficient, the sign and magnitude of which are determined by the maximum temperature difference △Tmax between clusters.

[0036] Specifically, this algorithm is the core of generating refined control instructions for each flow regulation unit. First, the formula for calculating the heat demand Hi has profound physical implications. The numerator (Ti-min(Ti)) represents the temperature difference between the i-th battery cluster and the current coldest cluster, and the denominator ΔTmax represents the maximum temperature difference of the system. Therefore, Hi is actually a normalized relative heat index, eliminating the influence of absolute temperature and purely reflecting the "relative contribution" of each cluster to the current system temperature difference. From this formula, we know that the heat demand of the coldest cluster is 0, the heat demand of the hottest cluster is 1, and the heat demand of other clusters is between 0 and 1, quantitatively reflecting the relative cooling demand of each cluster. This normalization makes Hi a universal index, accurately characterizing the relative cooling demand of each cluster regardless of the system temperature level. Second, the calculation of the opening compensation value ΔKi=α×Hi transforms the heat demand into specific execution instructions.

[0037] The three-way mixing valve has a base opening Kset (e.g., 50%). Based on this, the opening compensation value ΔKi is calculated to obtain the actual opening: Kset_i = Kset + ΔKi. The temperature difference adjustment coefficient α is determined as follows: When ΔTmax exceeds a preset threshold, α takes a positive value. At this time, the actual opening Kset_i is proportional to the heat demand Hi. The hottest cluster receives the maximum opening, i.e., the maximum cooling flow, while the coldest cluster receives the minimum opening, i.e., the minimum cooling flow, achieving on-demand allocation of cooling resources. When ΔTmax is within the normal range, α can be set to 0, and the flow of each cluster returns to a balanced state. The magnitude of α is positively correlated with the degree to which ΔTmax exceeds the threshold; that is, the larger ΔTmax is, the larger the value of α is, ensuring stronger adjustment when the temperature difference is greater. This control strategy based on heat demand and dynamic coefficients achieves intelligent allocation of limited cooling resources, adaptively addressing thermal imbalance problems under various operating conditions, and fundamentally eliminating the hidden danger of local overheating.

[0038] It is understood that the above embodiments only illustrate preferred embodiments of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can freely combine the above technical features without departing from the concept of the present invention, and can also make several modifications and improvements, all of which fall within the protection scope of the present invention. Therefore, all equivalent transformations and modifications made with respect to the scope of the claims of the present invention should fall within the scope of the claims of the present invention.

Claims

1. A temperature control system for an energy storage system, characterized in that, Includes a chiller unit (1) and multiple battery clusters connected in parallel, each of the battery clusters including at least one battery pack (9). It also includes a primary liquid cooling pipeline supply pipe (2) and a primary liquid cooling pipeline return pipe (3) connected to the chiller unit (1), a secondary liquid cooling pipeline supply pipe (5) and a secondary liquid cooling pipeline return pipe (6) corresponding to each battery cluster, and a tertiary liquid cooling pipeline supply pipe (7) and a tertiary liquid cooling pipeline return pipe (8) corresponding to each battery pack (9). Its characteristic is that it further includes: Multiple temperature sensors are provided, with one temperature sensor corresponding to each battery pack (9) for collecting temperature data of the corresponding battery pack; Multiple flow regulation units, each of which is located at the connection between the secondary liquid cooling pipeline return water pipe (6) and the primary liquid cooling pipeline return water pipe (3) of the corresponding battery cluster, are used to regulate the flow rate of the cooling medium to the corresponding battery cluster. The controller is communicatively connected to the plurality of temperature sensors and electrically connected to the chiller unit (1) and the plurality of flow regulating units; the controller is used to control the opening degree of the flow regulating units and the outlet water temperature of the chiller unit according to the temperature data.

2. The temperature control system for an energy storage system according to claim 1, characterized in that, The flow regulation unit is a three-way mixing valve (4), which has a first inlet, a second inlet and an outlet. The first inlet is connected to the upstream section of the primary liquid cooling pipeline return water pipe (3), the second inlet is connected to the secondary liquid cooling pipeline return water pipe (6) corresponding to the battery cluster, and the outlet is connected to the downstream section of the primary liquid cooling pipeline return water pipe (3).

3. The temperature control system for an energy storage system according to claim 1, characterized in that, The chiller unit (1) includes a circulating water pump, which drives the cooling medium to flow in the primary liquid cooling pipeline supply pipe (2), the primary liquid cooling pipeline return pipe (3), the secondary liquid cooling pipeline supply pipe (5), the secondary liquid cooling pipeline return pipe (6), the tertiary liquid cooling pipeline supply pipe (7), and the tertiary liquid cooling pipeline return pipe (8).

4. The temperature control system for an energy storage system according to claim 1, characterized in that, The inlet end of the secondary liquid cooling pipeline water supply pipe (5) is connected to the primary liquid cooling pipeline water supply pipe (2), and the outlet end of the secondary liquid cooling pipeline water supply pipe (5) is connected to the inlet end of the tertiary liquid cooling pipeline water supply pipe (7).

5. A temperature control method for an energy storage system, applied to the temperature control system according to any one of claims 1 to 4, characterized in that, Includes the following steps: Step S1: Collect temperature data of each battery pack using the multiple temperature sensors; Step S2: Based on the temperature data, control the opening degree of the flow regulation unit and the outlet water temperature of the chiller unit (1) to independently regulate the flow rate and temperature of the cooling medium flowing to each battery cluster.

6. The temperature control method for an energy storage system according to claim 5, characterized in that, Step S2 includes: The representative temperature Ti of each battery cluster is obtained based on the temperature data. Based on the representative temperature Ti, calculate the temperature deviation ΔTdevi of each battery cluster and the maximum temperature difference ΔTmax between clusters; Based on the temperature deviation △Tdevi, calculate the temperature setting compensation value △Tseti for each battery cluster; Based on the maximum temperature difference between clusters △Tmax and the representative temperature Ti of each battery cluster, the opening compensation value △Ki is calculated for the flow regulation unit corresponding to each battery cluster. The outlet water temperature of the chiller unit (1) is adjusted according to the temperature setting compensation value △Tseti. The opening degree of the flow regulation unit of the corresponding battery cluster is adjusted according to the opening degree compensation value △Ki.

7. The temperature control method for an energy storage system according to claim 6, characterized in that, The representative temperature Ti is the highest temperature of all cells in the corresponding battery cluster.

8. The temperature control method for an energy storage system according to claim 7, characterized in that, The temperature deviation ΔTdevi = Ti - Tavg, where Tavg is the average value of the representative temperatures of all battery clusters; the maximum temperature difference between clusters ΔTmax = max(Ti) - min(Ti), where max(Ti) is the maximum value among the representative temperatures of all battery clusters, and min(Ti) is the minimum value among the representative temperatures of all battery clusters.

9. The temperature control method for an energy storage system according to claim 7, characterized in that, The temperature set compensation value ΔTseti is calculated using the following formula: △Tseti=-Kp×△Tdevi-Kd×(△Tdevi-△Tdevi_pre) Where Kp and Kd are control coefficients, and △Tdevi_pre is the temperature deviation of the previous cycle.

10. The temperature control method for an energy storage system according to claim 6, characterized in that, The opening compensation value ΔKi is calculated through the following steps: Calculate the heat demand Hi for each battery cluster, where Hi = (Ti - min(Ti)) / ΔTmax; The opening compensation value △Ki is calculated based on the heat demand Hi, where △Ki = α × Hi, α is the temperature difference adjustment coefficient, and its sign and magnitude are determined by the maximum temperature difference between clusters △Tmax.

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