A heat dissipation control method for energy storage system

Abstract

The present invention relates to the technical field of energy storage cabinets, and more specifically, to a method for controlling heat dissipation of an energy storage system. An energy storage system comprises a cabinet, a battery pack, a controller, and a liquid cooling system. The liquid cooling system comprises a liquid cooling host and several heat exchangers connected to the liquid cooling host. The interior of the cabinet is divided into a battery room, a control room, a cooling room, and a main control room by partitions. The battery pack, the controller, and the liquid cooling host are respectively installed in the battery room, the control room, and the cooling room. Several heat exchangers are distributed in the control room and the battery room. The main control room is provided with a main switch. The energy storage system places the controller and battery pack, which generate more heat, in a control room and a battery room, which are independent of each other. At the same time, heat exchangers connected to the water cooling host are respectively provided in the control room and the battery room. This allows the heat in the control room and the battery room to be exchanged with the heat exchanger, thereby achieving the effect of separate heat dissipation in the two chambers.

Description

Technical Field

[0001] The present invention relates to the technical field of energy storage cabinets, and in particular to a heat dissipation control method for an energy storage system. Background Art

[0002] During the operation of the energy storage system, the battery module and power controller are core components, and their operating performance is closely related to temperature. However, due to significant differences in their material properties, thermal capacity, and power-temperature response curves, the optimal operating power of the battery and controller are often out of sync under the same heat dissipation conditions. Specifically, when the battery temperature rises to a certain threshold, its maximum allowable charge and discharge power will be subject to thermal safety requirements and forced to operate at a reduced rating; at the same time, the controller may still have a higher power output capability at the same ambient temperature. This power output mismatch limits the overall performance of the energy storage system to the lower value of the optimal power of the battery and controller, resulting in a significant loss of system efficiency.

[0003] Existing liquid cooling solutions typically employ fixed-ratio power allocation strategies or independent control based on temperature feedback from individual components, failing to fully consider the dynamic thermal coupling between the battery and controller. For example, these solutions only regulate the temperature of the battery module without addressing the coordinated optimization of the controller. Global temperature balancing strategies have also been proposed, which, while reducing the maximum system temperature through temperature balancing, fail to address the power compatibility issues of different components at specific temperatures.

[0004] Therefore, there is an urgent need for an intelligent heat dissipation control method that can identify the optimal power characteristics of the battery and controller at their respective temperatures in real time, and dynamically allocate the heat dissipation resources of the liquid cooling system so that the power output capabilities of the two are always synchronized and matched, thereby breaking through the system performance bottleneck caused by the limitations of thermal management strategies in existing technologies. Summary of the Invention

[0005] The object of the present invention is to provide a method for controlling heat dissipation of an energy storage system, which can reasonably distribute heat dissipation power.

[0006] The embodiments of the present invention are achieved through the following technical solutions:

[0007] An energy storage system includes a cabinet, a battery pack, a controller, and a liquid cooling system; the liquid cooling system includes a liquid-cooled host and several heat exchangers connected to the liquid-cooled host; the interior of the cabinet is divided into a battery room, a control room, a cooling room, and a main control room by partitions; the battery pack, controller, and liquid-cooled host are respectively installed in the battery room, control room, and cooling room; several heat exchangers are distributed in the control room and battery room; and the main control room is provided with a main switch.

[0008] Furthermore, the control room is provided with a heat exchange box; ventilation holes are provided at both ends of the heat exchange box; a fan and the heat exchanger are provided inside the heat exchange box between the ventilation holes at both ends, so that the air in the control room circulates through the heat exchanger.

[0009] Furthermore, a plurality of battery packs are arranged in the battery chamber; each of the battery packs is connected to one of the heat exchangers.

[0010] Furthermore, the heat exchanger is connected to the liquid cooling host through a pipeline; and each pipeline of the heat exchanger is provided with a proportional regulating valve.

[0011] A heat dissipation control method for an energy storage system includes: obtaining battery temperature and controller temperature in real time; determining the current optimal power of the two based on a pre-stored temperature-power relationship; and dynamically adjusting the heat dissipation power distribution of a liquid cooling system so that the difference between the current optimal power of the battery and the controller is less than a set threshold.

[0012] Furthermore, the heat dissipation power distribution is achieved by changing the refrigerant flow of the battery heat dissipation branch and the controller heat dissipation branch through a proportional control valve.

[0013] Furthermore, the temperature-power relationship is calibrated through experiments, including charge and discharge derating curves of the battery at different temperatures and charge and discharge derating curves of the controller at different temperatures.

[0014] Furthermore, the current power of the system is monitored; within the maximum total cooling power, the temperature control targets of the control room and the battery room ensure that the optimal power of both is 1.2 times the current power of the system.

[0015] Furthermore, if the battery temperature approaches a safety threshold, priority is given to ensuring the heat dissipation power of the battery.

[0016] Furthermore, if the temperature of either the battery pack or the controller exceeds a safety threshold, full flow cooling of the component is forced.

[0017] The technical solutions of the embodiments of the present invention have at least the following advantages and beneficial effects:

[0018] The energy storage system of this invention places the controller and battery pack, which generate relatively high amounts of heat, in separate control and battery compartments. Heat exchangers connected to the water-cooled main unit are installed in each compartment. This allows heat from both the control and battery compartments to be exchanged with the heat exchangers, achieving independent heat dissipation within the two compartments. Each heat exchanger is equipped with a proportional control valve to precisely control the refrigerant flow within each heat exchanger, enabling even more precise temperature control of both compartments.

[0019] Furthermore, the energy storage system's heat dissipation control method aims to achieve the same optimal power output for the controller and battery pack at the target temperature. This ensures that the refrigerant flow rates allocated to the control room and battery room are aligned to achieve the same optimal power output for the controller and battery pack. This method can identify the optimal power characteristics of the battery and controller at their respective temperatures in real time and dynamically allocate the cooling system's heat dissipation resources to ensure a consistent and synchronized power output between the two. This overcomes the system performance bottlenecks caused by the limitations of existing thermal management strategies. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is an outline diagram of the energy storage system of the present invention.

[0021] Figure 2 Schematic diagram of the internal structure of the energy storage system of the present invention.

[0022] Figure 3 Schematic diagram of the internal structure of the heat exchange box.

[0023] Figure 4 This is the framework diagram of the heat dissipation control system.

[0024] Figure numerals: 1-cabinet, 2-battery pack, 3-controller, 4-liquid cooling host, 5-heat exchanger, 6-partition, 7-battery room, 8-control room, 9-cooling room, 10-main control room, 11-main switch, 12-heat exchange box, 13-ventilation hole, 14-fan. DETAILED DESCRIPTION

[0025] like Figures 1-4 As shown, this embodiment provides an energy storage system, including a cabinet 1, a battery pack 2, a controller 3 and a liquid cooling system. The liquid cooling system includes a liquid cooling host 4 and several heat exchangers 5 connected to the liquid cooling host 4. The heat exchanger 5 is connected to the liquid cooling host 4 through a pipe. The pipe of each heat exchanger 5 is provided with a proportional regulating valve. The liquid cooling host 4 is used to pump the refrigerant to each heat exchanger 5. The refrigerant exchanges heat with the battery pack 2 or the air in the control room 8 at the heat exchanger 5, thereby taking away the heat generated by the battery pack 2 and the controller 3. The purpose of heat dissipation is thereby achieved. The heat taken away by the refrigerant is released in the liquid cooling host 4, thereby causing the refrigerant to cool again, and then can flow to the control room 8 or the battery room 7 again to take away the heat.

[0026] The interior of the cabinet 1 is divided by partitions 6 into a battery compartment 7, a control compartment 8, a cooling compartment 9, and a main control room 10. These four compartments are independent of each other, allowing for independent temperature control without interfering with each other. The battery packs 2, controller 3, and liquid cooling unit 4 are installed in the battery compartment 7, control compartment 8, and cooling compartment 9, respectively. Several heat exchangers 5 are located in the control compartment 8 and battery compartment 7. Specifically, the battery compartment 7 houses several battery packs 2. Each battery pack 2 is connected to a heat exchanger 5 below. The battery packs 2 fit snugly against the heat exchangers 5, ensuring that heat generated by the battery packs 2 is promptly and stably transferred to the heat exchangers 5. The heat exchangers 5 in the control compartment 8 are exposed to the air, allowing the air to cool down upon contact with the heat exchangers 5. The main control room 10 is equipped with a main switch 11, which controls the connection between the entire energy storage system and the outside world. When the main switch 11 is off, the energy storage system is disconnected from the external power grid. Similarly, when the main switch 11 is on, the energy storage system is effectively connected to the external power grid.

[0027] During operation, the controller 3 in the control room 8 controls the charge and discharge power of the battery pack 2. During operation, both the controller 3 and the battery pack 2 generate a significant amount of heat. The liquid cooling unit 4 delivers refrigerant to the control room 8 and the battery compartment 7, removing the heat from these two chambers to the liquid cooling unit 4. The liquid cooling unit 4 is equipped with a cooling fan that cools the heat-absorbing refrigerant through air cooling, thus enabling the liquid cooling system to be recycled. This effectively dissipates heat from the controller 3 and the battery pack 2.

[0028] The energy storage system of the present invention places the controller 3 and battery pack 2, which generate relatively high amounts of heat, in the independent control room 8 and battery room 7, respectively. Heat exchangers 5 connected to the water-cooled main unit are also installed in each of these rooms. This allows heat within both the control room 8 and the battery room 7 to be exchanged with the heat exchangers 5, achieving the effect of independent heat dissipation in both chambers. Each heat exchanger 5 is equipped with a proportional control valve, enabling precise control of the refrigerant flow within each heat exchanger 5. This allows for more precise temperature control of both chambers.

[0029] In this embodiment, the control room 8 is provided with a heat exchange box 12. The heat exchange box 12 is tubular and has ventilation holes 13 at both ends. A fan 14 and a heat exchanger 5 are provided inside the heat exchange box 12 between the ventilation holes 13 at both ends. When the fan 14 is in operation, it draws air from the control room 8 through the ventilation holes 13 at one end of the heat exchange box 12 and sends it to the heat exchanger 5. When the hot air passes through the heat exchanger 5, it exchanges heat with the refrigerant inside the heat exchanger 5, thereby dissipating heat from the airflow. The cooled airflow flows out to the control room 8 through the ventilation holes at the other end of the heat exchange box 12. The air in the control room 8 circulates through the heat exchanger 5, thereby continuously dissipating heat from the air in the control room 8. This can also dissipate heat from the controller 3 in the control room 8, allowing the controller 3 to operate in a lower temperature range.

[0030] This embodiment also provides a method for controlling heat dissipation in an energy storage system, comprising: obtaining the temperature of the battery and the temperature of the controller 3 in real time; determining the current optimal power of the two based on a pre-stored temperature-power relationship; and dynamically adjusting the heat dissipation power distribution of the liquid cooling system to ensure that the difference between the current optimal power of the battery and the controller 3 is less than a set threshold.

[0031] Specifically, follow the steps below: Step 1: Real-time acquisition of battery temperature T bat and controller 3 temperature T ctrl ;

[0032] Step 2: Query the pre-stored temperature-power relationship table to obtain the current T bat The corresponding maximum allowable battery power Pmaxbat, and T ctrl The corresponding maximum output power of controller 3 is Pmax ctrl;

[0033] Step 3: Calculate the power deviation ΔP = |Pmax bat − Pmax ctrl|. If ΔP > δ (set threshold), proceed to step 4.

[0034] Step 4: Adjust the liquid cooling system's bypass valve to allow more refrigerant to flow to the lower-power side. If Pmax bat < Pmaxctrl, increase the refrigerant flow to the battery branch until ΔP ≤ δ.

[0035] In addition, the heat dissipation control method of the energy storage system aims to make the optimal power of the controller 3 and the battery pack 2 the same at the target temperature under control, so that the refrigerant flow rate allocated to the control room 8 and the battery room 7 is the same as the optimal power of the controller 3 and the battery pack 2. It is able to identify the optimal power characteristics of the battery and the controller 3 at their respective temperatures in real time, and by dynamically allocating the heat dissipation resources of the liquid cooling system, the power output capabilities of the two are always kept synchronously matched, thereby breaking through the system performance bottleneck caused by the limitations of thermal management strategies in the prior art. For example, when the battery needs to be derated due to high temperature, the controller 3 can still output a higher power, resulting in the overall performance of the system being limited by the battery. At this time, the refrigerant flow rate of the control room 8 is reduced and the refrigerant flow rate of the battery room 7 is increased, so that the temperature of the battery pack 2 is reduced and the temperature of the controller 3 is appropriately increased, so that the current optimal working power of the two is equivalent or the same.

[0036] In order to effectively implement the heat dissipation control method of the energy storage system, a heat dissipation control system is also provided. Figure 4As shown, it includes a control chip, a temperature acquisition module, a power query module, a deviation calculation module and a valve body adjustment module. The control chip is used for overall control and can adopt an STM32H743 chip. The temperature acquisition module includes several temperature sensors. The temperature sensor of the control room 8 is installed inside the control room 8 or installed in contact with the main heating part. The temperature sensor of the battery room 7 is installed inside the battery room 7 or installed in contact with the heating part of the battery pack 2. The power query module queries the temperature-power relationship table to determine the current T bat The corresponding maximum allowable battery power Pmax bat and T ctrl The corresponding maximum output power of controller 3 is Pmax ctrl. The deviation calculation module calculates the power deviation ΔP = |Pmax bat − Pmax ctrl| and determines whether ΔP is greater than the set threshold δ. The valve adjustment module is a proportional control valve. Cooling power distribution is achieved by adjusting the refrigerant flow rate between the battery cooling branch and the controller 3 cooling branch through the proportional control valve.

[0037] It should also be noted that the temperature-power relationship table can be based on the factory-calibrated performance parameters of the battery or controller 3, or it can be based on performance parameters summarized through independent experiments. During subsequent use, the system can modify the performance parameters based on actual conditions, ensuring real-time adjustment to the most accurate state. This prevents performance parameter changes caused by device aging from affecting the accuracy of system decisions. The temperature-power relationship table includes the charge and discharge derating curves for the battery at different temperatures and the charge and discharge derating curves for the controller 3 at different temperatures.

[0038] The threshold δ can be set as needed. For example, if δ is set to 500 watts, when the difference between the optimal power of the battery and the optimal power of the controller 3 reaches 500 watts, the refrigerant flow to the controller 3 and the battery pack 2 is adjusted, thereby causing the temperature of the controller 3 and the battery pack 2 to change and causing the difference between the optimal power of the battery and the optimal power of the controller 3 to be less than 500 watts after the change. The value of δ can be set to other values ​​as needed.

[0039] In this embodiment, the current power of the monitoring system is monitored. Within the maximum total cooling power, the temperature control targets of the control room 8 and the battery room 7 ensure that the optimal power of both is 1.2 times the current power of the system. The maximum heat dissipation capacity of the liquid cooling system is Qmax, the heat dissipation power of the battery is Qbat, and the heat dissipation power of the controller 3 is Qctrl. During the control process, it must be ensured that Qbat+Qctrl≤Qmax. On this basis, the optimal power of the controller 3 and the battery pack 2 is guaranteed to be 1.2 times the current actual power, so that the energy storage system can respond to fluctuations and sudden changes in the system load in a timely manner, ensuring the adaptability of the energy storage system.

[0040] In this embodiment, if the battery temperature approaches a safety threshold, priority is given to ensuring the battery's heat dissipation power, thereby better protecting the battery from damage. If either the battery pack 2 or controller 3 temperature exceeds the safety threshold, full cooling of that component is forced. This prevents temperature overshoots in a timely manner, effectively ensuring system safety and reducing equipment damage.

Claims

1. A heat dissipation control method for an energy storage system, implemented based on an energy storage system, characterized in that: The energy storage system includes a cabinet, a battery pack, a controller, and a liquid cooling system; the liquid cooling system includes a liquid cooling host and several heat exchangers connected to the liquid cooling host; the interior of the cabinet is divided into a battery room, a control room, a cooling room, and a main control room by partitions; the battery pack, controller, and liquid cooling host are respectively installed in the battery room, control room, and cooling room; several heat exchangers are distributed in the control room and battery room; and the main control room is provided with a main switch; The heat dissipation control method for the energy storage system is as follows: obtaining the battery temperature and controller temperature in real time; determining the current optimal power of the two based on the pre-stored temperature-power relationship; and dynamically adjusting the heat dissipation power distribution of the liquid cooling system so that the current optimal power difference between the battery and the controller is less than the set threshold.

2. The heat dissipation control method of the energy storage system according to claim 1, characterized in that: The control room is provided with a heat exchange box; ventilation holes are provided at both ends of the heat exchange box; a fan and the heat exchanger are provided inside the heat exchange box between the ventilation holes at both ends, so that the air in the control room circulates through the heat exchanger.

3. The heat dissipation control method of the energy storage system according to claim 2, characterized in that: Several battery packs are arranged in the battery room; each of the battery packs is connected to one of the heat exchangers.

4. The heat dissipation control method of the energy storage system according to claim 3, characterized in that: The heat exchanger is connected to the liquid cooling host through a pipeline; each pipeline of the heat exchanger is provided with a proportional regulating valve.

5. The heat dissipation control method of the energy storage system according to claim 4, characterized in that: The heat dissipation power distribution is achieved by changing the refrigerant flow of the battery heat dissipation branch and the controller heat dissipation branch through a proportional control valve.

6. The heat dissipation control method of the energy storage system according to claim 5, characterized in that: The temperature-power relationship is calibrated through experiments, including charge and discharge derating curves of the battery at different temperatures and charge and discharge derating curves of the controller at different temperatures.

7. The method for controlling heat dissipation of an energy storage system according to claim 6, wherein: Monitor the current power of the system; within the maximum total cooling power, the temperature control target of the control room and battery room ensures that the optimal power of both is 1.2 times the current power of the system.

8. The heat dissipation control method of the energy storage system according to claim 7, characterized in that: If the battery temperature approaches the safety threshold, priority is given to ensuring the battery's heat dissipation power.

9. The heat dissipation control method of the energy storage system according to claim 8, characterized in that: If the temperature of the battery pack or controller exceeds the safety threshold, full flow cooling is forced on the component whose temperature exceeds the safety threshold.

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