Energy storage valve temperature control system

Abstract

The invention relates to an energy storage valve temperature control system, and belongs to the technical field of energy storage. Each energy storage valve cooling branch of the system comprises a battery box cooling branch, a power module cooling branch and a deionized water treatment unit, the battery box cooling branch and the power module cooling branch are connected in series and then connected into a cooling unit, and a liquid outlet of the battery box cooling branch is communicated with a liquid inlet of the power module cooling branch. The liquid inlet of the power module cooling branch is also communicated with the liquid outlet of the deionized water treatment unit; and the liquid inlet of the deionized water treatment unit is connected between the cooling unit and the liquid inlet of the battery box cooling branch. The problems that for cooled units with different requirements for tolerable temperature and conductivity, an existing temperature control system cannot conduct refrigeration according to actual requirements, and the requirements for the conductivity of the different cooled units cannot be met are solved.

Description

Technical Field

[0001] The invention relates to an energy storage valve temperature control system, belonging to the technical field of energy storage. Background Art

[0002] Independent energy storage power stations are mainly divided into two types: warehouse type and station type. As the scale of energy storage project construction continues to increase, the capacity of battery cells and the energy density of the system are also increasing. Even if large-capacity batteries are used, the construction of a 100-megawatt energy storage project still requires hundreds of thousands or even hundreds of thousands of batteries to be combined together, which will generate more heat and put forward higher requirements for the temperature control management of the energy storage system. The energy storage battery system has large battery capacity and power, and high power density has high requirements for heat dissipation. The energy storage system is prone to problems such as battery heat generation and uneven temperature distribution. Therefore, temperature control is extremely important for the life and safety of the battery system.

[0003] Battery boxes, power modules, VSC flexible direct current modules, etc. all generate a lot of heat during operation and need to be cooled. Since the energy storage valve-battery box, energy storage valve-power module, and energy storage valve-VSC flexible direct current module have different requirements for cooling water conductivity and different tolerance temperatures, they also have different requirements for inlet water temperature. It is often necessary to configure multiple sets of temperature control equipment with different functions for cooling. At the same time, energy storage temperature control equipment accounts for 40%-80% of the energy consumption in the auxiliary system. Under the premise of ensuring the life and safety of the battery system, how to improve the operating efficiency of the temperature control system has become a key issue.

[0004] The Chinese patent application publication document with publication number CN116885331A discloses a temperature control system for energy storage batteries and an energy storage battery cabinet, in which the cooled units are connected in parallel, and the temperature of the liquid inlet of each cooled unit is the same. However, for cooled units with different tolerance temperature or conductivity requirements, such as energy storage valve-battery box and energy storage valve-power module, the system needs to consider many factors when performing corresponding temperature control on different cooled units, and the control is relatively complicated, and the conductivity requirements of different cooled units cannot be met. Summary of the invention

[0005] The object of the present invention is to provide a temperature control system for an energy storage valve, so as to solve the problem that for cooled units with different tolerance temperature and conductivity requirements, the existing temperature control system cannot perform refrigeration according to actual needs and cannot meet the conductivity requirements of different cooled units.

[0006] To achieve the above object, the solution of the present invention includes: A storage valve temperature control system of the present invention includes a refrigeration unit and a cooling unit. The refrigeration unit provides cooling energy for the cooling unit. The cooling unit is connected to at least one storage valve cooling branch. Each storage valve cooling branch includes a battery box cooling branch, a power module cooling branch and a deionized water treatment unit. The battery box cooling branch and the power module cooling branch are connected in series and then connected to the cooling unit. The liquid outlet of the battery box cooling branch is connected to the liquid inlet of the power module cooling branch. The liquid inlet of the power module cooling branch is also connected to the liquid outlet of the deionized water treatment unit. The liquid inlet of the deionized water treatment unit is connected between the cooling unit and the liquid inlet of the battery box cooling branch.

[0007] Furthermore, the cooling unit includes an external cooling unit and an internal cooling unit. One side of the external cooling unit realizes heat exchange with the refrigeration unit through an evaporator, and the other side realizes heat exchange with the internal cooling unit through a partition heat exchanger. The internal cooling unit is connected to the energy storage valve cooling branch to realize heat exchange between the battery box cooling branch and the power module cooling branch.

[0008] Further, when there are at least two cooling branches of the energy storage valve, each cooling branch of the energy storage valve is connected in parallel and communicated with the internal cooling unit.

[0009] Furthermore, the external cooling unit includes an external circulation pump, a filter and a first pressure stabilizing unit, the liquid outlet of the external circulation pump returns to the liquid inlet of the external circulation pump through the second channel of the evaporator, the filter and the first channel of the partition-type heat exchanger, and the first pressure stabilizing unit is arranged between the liquid outlet of the partition-type heat exchanger and the liquid inlet of the external circulation pump, wherein the first channel of the evaporator is connected in series in the refrigeration unit, and the second channel of the partition-type heat exchanger is connected in series in the internal cooling unit.

[0010] Furthermore, the external cooling unit also includes a first water replenishment unit, which includes a water storage tank, a water replenishment pump and a check valve. The water replenishment pump is arranged between the water storage tank and the check valve, and the first water replenishment unit is arranged between the liquid outlet of the pressure stabilizing unit and the liquid inlet of the external circulation pump.

[0011] Furthermore, the internal cooling unit is provided with a heater and an internal circulation pump corresponding to each energy storage valve cooling branch, and each energy storage valve cooling branch is connected to the second channel of the partition heat exchanger after being connected in parallel with the corresponding heater and internal circulation pump; each energy storage valve cooling branch is provided with a corresponding second pressure stabilizing unit.

[0012] Furthermore, the energy storage valve cooling branch also includes a second water replenishment unit, which includes a water storage tank, a water replenishment pump and a check valve. The water replenishment pump is arranged between the water storage tank and the check valve, and the second water replenishment unit is arranged at the liquid inlet of the deionized water treatment unit.

[0013] Furthermore, both the external circulation pump and the internal circulation pump adopt two circulation pumps arranged in parallel to achieve redundant arrangement of the external circulation pump and the internal circulation pump.

[0014] Furthermore, each energy storage valve cooling branch also includes a VSC power module cooling branch, the VSC power module cooling branch is connected in series with the battery box cooling branch and the power module cooling branch, and the liquid inlet of the VSC power module cooling branch is connected to the liquid outlet of the power module cooling branch.

[0015] Furthermore, a precision filter is provided between the liquid outlet of the deionized water treatment unit and the liquid inlet of the power module cooling branch.

[0016] The beneficial effects of the present invention are as follows: as an improved invention, the energy storage valve cooling branch of the energy storage valve temperature control system includes a battery box cooling branch, a power module cooling branch and a deionized water treatment unit, the liquid outlet of the battery box cooling branch is the liquid inlet of the power module cooling branch, satisfying the requirement that the water inlet temperature required by the battery box cooling branch is lower than the water inlet temperature required by the power module cooling branch; in addition, the liquid inlet of the power module cooling branch is also connected to the liquid outlet of the deionized water treatment unit, the liquid inlet of the deionized water treatment unit is connected between the cooling unit and the liquid inlet of the battery box cooling branch, and the conductivity requirement of the power module cooling branch is met by adjusting the liquid outlet size of the deionized water treatment unit. Therefore, the present invention solves the problem that for cooling branches with different tolerance temperatures or conductivity requirements, the existing temperature control system cannot perform refrigeration according to actual needs, nor can it meet the conductivity requirements of different cooling branches. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a process flow chart of a single set of energy storage valve temperature control system; Figure 2 It is a process flow chart of multiple energy storage valve temperature control systems; Figure 3 It is a process flow chart of multiple energy storage battery temperature control systems using nitrogen pressure stabilization; Figure 4 It is a process flow chart of multiple energy storage battery temperature control systems using wound electric heaters. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is described in detail in a clear and complete manner in conjunction with the accompanying drawings and embodiments.

[0019] The idea of ​​the present invention is that the energy storage valve cooling branch of the energy storage valve temperature control system includes a battery box cooling branch, a power module cooling branch and a deionized water treatment unit, the liquid outlet of the battery box cooling branch is connected to the liquid inlet of the power module cooling branch, in addition, the liquid outlet of the deionized water treatment unit is connected to the liquid inlet of the power module cooling branch, and the liquid inlet of the deionized water treatment unit is connected between the cooling unit and the liquid inlet of the battery box cooling branch.

[0020] System Example: like Figure 1 As shown, a storage valve temperature control system of the present invention includes a refrigeration unit, a cooling unit and a storage valve cooling branch. The storage valve cooling branch includes a storage valve-battery box cooling branch (referred to as the battery box cooling branch), a storage valve-power module cooling branch (referred to as the power module cooling branch) and a deionized water treatment unit. As another embodiment, the storage valve cooling branch also includes a storage valve-VSC power module cooling branch (referred to as the VSC power module cooling branch). According to the requirements for the temperature and conductivity of the cooling water, the battery box cooling branch and the power module cooling branch are connected. After being connected in series with the VSC power module cooling branch, it is connected to the cooling unit. The outlet of the battery box cooling branch is connected to the inlet of the power module cooling branch, the inlet of the power module cooling branch is connected to the outlet of the deionized water treatment unit, the inlet of the VSC power module cooling branch is connected to the outlet of the power module cooling branch, and the inlet of the deionized water treatment unit is connected between the cooling unit and the inlet of the battery box cooling branch. Through reasonable configuration of the process, integrated cooling is achieved, the operating efficiency of the temperature control system is improved, and its energy consumption proportion in the auxiliary system is reduced.

[0021] The cooling unit includes an external cooling unit and an internal cooling unit. One side of the external cooling unit realizes heat exchange with the refrigeration unit through the evaporator, and the other side realizes heat exchange with the internal cooling unit through the partition heat exchanger. The internal cooling unit is connected to the energy storage valve cooling branch to realize heat exchange between the battery box cooling branch, the power module cooling branch and the VSC power module cooling branch. When there are at least two energy storage valve cooling branches, each energy storage valve cooling branch is connected in parallel with the internal cooling unit (such as Figure 2 as shown).

[0022] Specifically, the refrigeration unit includes a compressor, a condenser, a regulating valve and an evaporator, wherein the compressor, the condenser and the regulating valve are connected in series in sequence and connected to the two ends of the evaporation side of the evaporator in the external cooling unit (also called the first channel of the evaporator). The evaporator also includes a heat exchange side (also called the second channel of the evaporator), and the heat exchange side is connected in series in the external cooling cycle. The working principle of the refrigeration unit is: the compressor compresses the gaseous refrigerant into a high-temperature and high-pressure gas, sends it to the condenser for cooling, and becomes a medium-temperature and high-pressure liquid refrigerant after being cooled by the environment. After entering the throttling component (regulating valve) for throttling and pressure reduction, it becomes a low-temperature and low-pressure gas-liquid mixture. The gas-liquid mixture absorbs the heat of the external cooling unit through the evaporator and vaporizes into a gaseous state, and then returns to the compressor for compression, and continues to circulate for refrigeration. Among them, the refrigeration unit can adopt compressor refrigeration, and the compressor can adopt various forms such as scroll type and rotor type; the condenser can adopt various forms such as copper tube aluminum fin heat exchanger, parallel flow microchannel radiator, etc.; the throttling component regulating valve can be a thermal expansion valve, an electronic expansion valve, etc.; the evaporator adopts a plate heat exchanger or a shell and tube heat exchanger or other forms of partition heat exchanger.

[0023] The external cooling unit includes an external circulation pump, a valve, a filter, a partition heat exchanger, a first water supply unit, a first voltage stabilizing unit, pipelines and instrument sensors, wherein the external circulation pump is connected in series with the heat exchange side of the evaporator (also called the second channel of the evaporator) through a valve, and then connected to the input end of the circulation pump valve through a filter and the first channel of the partition heat exchanger to complete the closure of the external cooling unit. When refrigeration is required, the external cooling water is driven by the external circulation pump and transported to the evaporator of the refrigeration unit. The cooled external cooling water is supplied to the partition heat exchanger and absorbs heat in the partition heat exchanger to complete the entire cycle, and this cycle repeats. The external circulation pump and valve adopt a one-in-one redundant configuration. The circulation pump can be a centrifugal pump, a shielded pump, and other forms; the first water replenishment unit includes a water storage tank, a water replenishment pump, and a check valve. The water replenishment pump is connected in series between the water storage tank and the check valve. The first water replenishment unit is arranged between the liquid outlet of the pressure stabilizing unit and the liquid inlet of the circulation pump. When the system needs water replenishment, the water replenishment pump is turned on for water replenishment; the first pressure stabilizing unit is arranged between the output end of the partition heat exchanger and the input end of the external circulation pump, including a pressure stabilizing tank, valves, and instrument sensors. The pressure stabilizing tank can be a high-level water tank pressure stabilizer, or a bladder tank, a nitrogen pressure stabilizing tank (such as Figure 3 As shown in the figure, when the system pressure is lower than the gas replenishment value, the nitrogen pressure stabilizing system automatically replenishes gas to the system. When the system pressure is higher than the exhaust value, it automatically exhausts gas to the outside and is equipped with a safety pressure relief valve. When the opening pressure is reached, the system automatically releases pressure to ensure safe and stable operation of the system. ) and other gas pressure stabilizing tanks, the valve parts of the pressure stabilizing unit include exhaust valves, safety valves, etc.

[0024] Each energy storage valve cooling branch includes a battery box cooling branch, a power module cooling branch and a VSC power module cooling branch connected in series. The inlet of the power module cooling branch is also connected to the outlet of the deionized water treatment unit. The inlet of the deionized water treatment unit is connected between the cooling unit and the inlet of the battery box cooling branch. The deionized water treatment unit includes an ion exchanger, a precision filter, a one-way valve, a pipeline and an instrument sensor; the ion exchanger of the deionized water treatment unit is formed by a single unit or multiple units in parallel, with a built-in mixed bed resin. The conductivity of part of the internal cooling water is reduced after passing through the ion exchanger. At the same time, a precision filter is set at the outlet of the ion exchanger to prevent the ion exchange resin from leaking into the cooling unit circulation loop. The outlet of the deionized water treatment unit is connected to the inlet of the power module cooling branch. The conductivity of the inlet cooling medium of the power module cooling branch can be controlled by the ion exchanger inlet regulating valve.

[0025] The energy storage valve cooling branch also includes a filter, a valve pipeline unit, a second water replenishment unit, a second pressure stabilizing unit, and an instrument sensor. The second water replenishment unit includes a water storage tank, a water replenishment pump and a check valve. The water replenishment pump is arranged between the water storage tank and the check valve. The second water replenishment unit is arranged at the liquid inlet of the deionized water treatment unit. The water replenishment pump can be a centrifugal pump, a shielded pump and other forms. The water tank is provided with a liquid level gauge and a liquid level switch. The system is also provided with a one-way valve, a solenoid valve, etc. When water replenishment is required, the solenoid valve can be opened; the second pressure stabilizing unit is arranged between the output end of the VSC power module and the input end of the internal circulation pump, including a high-level water tank (which can also be a nitrogen pressure stabilizing tank, such as Figure 3 When the system pressure is higher than the set value, the pressure is released through the safety valve.

[0026] The internal cooling unit is provided with an internal circulation pump, valve components and a heating unit (heater) corresponding to each energy storage valve cooling branch. Each energy storage valve cooling branch is connected in parallel with the corresponding heater and internal circulation pump and then connected to the second channel of the partition wall heat exchanger (such as Figure 2As shown); Specifically, the output end of the internal circulation pump is connected to the heater after passing through the second channel of the partition heat exchanger. The output end of the heater is divided into two paths. One path passes through the main filter and is connected to the battery box cooling branch, the power module cooling branch and the VSC power module cooling branch on the energy storage valve cooling branch in turn, and then is connected back to the input end of the internal circulation pump. The other path passes through the check valve and is connected to the input end of the ion exchanger of the deionized water treatment unit. The output end of the ion exchanger is mixed with the outlet water of the battery box cooling branch and heated up and then enters the power module cooling branch and the VSC power module cooling branch in turn. When cooling is required, the internal cooling water is driven by the circulation pump and transported to the partition heat exchanger of the external cooling unit. The cooled internal cooling water is first supplied to the battery box cooling branch. The heated and heated internal cooling water is mixed with the outlet water of the deionized unit and then enters the power module cooling branch and the VSC power module cooling branch, and absorbs heat in the cooled device to complete the entire cycle, and this cycle repeats. The internal circulation pump and valve components are configured with one redundant configuration, and the circulation pump is a centrifugal pump, a shielded pump, and other forms; the heater of the heating unit can be a PTC plug-in type, a PTC winding type, and the like. When the ambient temperature is relatively low in winter, the electric heater is started to heat the circulating water and then supply it to the cooled unit to meet the temperature requirements of the cooled device, and this cycle is repeated (in this embodiment, the electric heater can be a PTC pipeline type, a PTC winding type, or a tank plug-in type, such as Figure 4 as shown).

[0027] The valve pipeline unit consists of a maintenance valve, a flow control valve, and a circulation pipeline.

[0028] The electrical control unit includes control and protection devices, temperature, pressure, flow, liquid level, conductivity and multiple sensors and control software; the control and protection devices can be in the form of PLC, single chip microcomputer, industrial computer, etc.; through the electrical control system, the intelligent and energy-saving of each control object of the energy storage valve cooling system can be realized. Including main pump redundancy switching function, fan energy-saving control, electric heating control function, automatic liquid filling function, automatic air filling and exhaust function, energy-saving control function, etc.

[0029] In this embodiment, environmentally friendly refrigerants such as R134a, R410a, R407C, R417A, R404A, and R507 are used as refrigerants; insulating media (such as a mixed solution of pure water + propylene glycol) are used as internal cooling water; according to environmental conditions, the external cooling system can use antifreeze in different proportions as the cooling medium and be equipped with an electric heater. At an ambient temperature of -30°C, the water supply temperature can still be guaranteed to be 20°C.

Claims

1. A storage valve temperature control system, comprising a refrigeration unit and a cooling unit, wherein the refrigeration unit provides cooling energy for the cooling unit, and the cooling unit is connected to at least one storage valve cooling branch, characterized in that: Each energy storage valve cooling branch includes a battery box cooling branch, a power module cooling branch and a deionized water treatment unit. The battery box cooling branch and the power module cooling branch are connected in series and then connected to the cooling unit. The liquid outlet of the battery box cooling branch is connected to the liquid inlet of the power module cooling branch. The liquid inlet of the power module cooling branch is also connected to the liquid outlet of the deionized water treatment unit. The liquid inlet of the deionized water treatment unit is connected between the cooling unit and the liquid inlet of the battery box cooling branch.

2. The energy storage valve temperature control system according to claim 1, characterized in that: The cooling unit includes an external cooling unit and an internal cooling unit. One side of the external cooling unit realizes heat exchange with the refrigeration unit through an evaporator, and the other side realizes heat exchange with the internal cooling unit through a partition heat exchanger. The internal cooling unit is connected to the energy storage valve cooling branch to realize heat exchange between the battery box cooling branch and the power module cooling branch.

3. The energy storage valve temperature control system according to claim 2, characterized in that: When there are at least two cooling branches of the energy storage valve, each cooling branch of the energy storage valve is connected in parallel and communicated with the internal cooling unit.

4. The energy storage valve temperature control system according to claim 2, characterized in that: The external cooling unit includes an external circulation pump, a filter and a first pressure stabilizing unit. The liquid outlet of the external circulation pump returns to the liquid inlet of the external circulation pump through the second channel of the evaporator, the filter and the first channel of the partition wall heat exchanger. The first pressure stabilizing unit is arranged between the liquid outlet of the partition wall heat exchanger and the liquid inlet of the external circulation pump, wherein the first channel of the evaporator is connected in series in the refrigeration unit, and the second channel of the partition wall heat exchanger is connected in series in the internal cooling unit.

5. The energy storage valve temperature control system according to claim 4, characterized in that: The external cooling unit also includes a first water replenishment unit, which includes a water storage tank, a water replenishment pump and a check valve. The water replenishment pump is arranged between the water storage tank and the check valve, and the first water replenishment unit is arranged between the liquid outlet of the pressure stabilizing unit and the liquid inlet of the external circulation pump.

6. The energy storage valve temperature control system according to claim 2, characterized in that: The internal cooling unit is provided with a heater and an internal circulation pump corresponding to each energy storage valve cooling branch. Each energy storage valve cooling branch is connected to the second channel of the partition heat exchanger after being connected in parallel with the corresponding heater and internal circulation pump; each energy storage valve cooling branch is provided with a corresponding second pressure stabilizing unit.

7. The energy storage valve temperature control system according to claim 6, characterized in that: The energy storage valve cooling branch also includes a second water replenishment unit, which includes a water storage tank, a water replenishment pump and a check valve. The water replenishment pump is arranged between the water storage tank and the check valve, and the second water replenishment unit is arranged at the liquid inlet of the deionized water treatment unit.

8. The energy storage valve temperature control system according to claim 4 or 6, characterized in that: The external circulation pump and the internal circulation pump both use two circulation pumps arranged in parallel to achieve redundant arrangement of the external circulation pump and the internal circulation pump.

9. The energy storage valve temperature control system according to claim 1, characterized in that: Each energy storage valve cooling branch also includes a VSC power module cooling branch, which is connected in series with the battery box cooling branch and the power module cooling branch, and the liquid inlet of the VSC power module cooling branch is connected to the liquid outlet of the power module cooling branch.

10. The energy storage valve temperature control system according to claim 1, characterized in that: A precision filter is also provided between the liquid outlet of the deionized water treatment unit and the liquid inlet of the power module cooling branch.

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