PCS temperature control assembly of energy storage system and energy storage system
By designing adaptive temperature control components at the PCS of the energy storage system, dynamically adjusting the flow rate of coolant, the problem of PCS temperature regulation in the prior art is solved, and more efficient cooling and energy consumption reduction is achieved.
Patent Information
- Application Number
- CN202421468983.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-25
- Publication Date
- 2025-04-25
- Estimated Expiration
- 2034-06-25
AI Technical Summary
In existing energy storage systems, the temperature regulation of PCS cannot be adaptive, resulting in the fixed flow rate and temperature of the coolant, which cannot meet the low temperature requirements of PCS, resulting in waste of energy and reduced system efficiency.
A PCS temperature control component is designed. By setting a second heat exchange structure and three liquid-cooled branches at the PCS, and setting a pipeline control valve on the third liquid-cooled branch, the flow rate of the coolant is dynamically adjusted according to the real-time temperature of the PCS to achieve adaptive temperature control.
By dynamically adjusting the flow rate of coolant, the lowest refrigeration power consumption can be achieved, ensuring that the PCS temperature does not exceed the maximum limit, improving the efficiency of the entire system and reducing energy consumption.
Smart Images
Figure CN222801903U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of liquid cooling energy storage systems, and specifically relates to an energy storage system PCS temperature control component and an energy storage system. Background Art
[0002] The energy storage system mainly includes the battery pack (Pack), the energy storage converter (PCS), the battery management system (BMS) and the energy management system (EMS), among which the Pack and PCS are the main heat-generating components. The traditional heat dissipation method of the energy storage system is air cooling, but the efficiency of air cooling is low, and it is limited by size and has high noise. In recent years, liquid cooling solutions have gradually emerged. At present, the energy storage system using the liquid cooling solution usually bypasses a liquid cooling pipeline in the Pack liquid cooling pipeline for the heat dissipation of the PCS. After the coolant is output from the liquid cooling unit, it dissipates the heat of the Pack and PCS respectively. At present, the flow rate and temperature of the coolant in the liquid cooling pipeline on the PCS side are usually fixed and cannot be adjusted. Since the temperature requirement of the PCS is lower than that of the Pack, when the heat generation power of the PCS is low, the fixed coolant flow rate and temperature will keep the PCS at a lower temperature, resulting in a certain degree of energy waste, making the energy consumption of the entire system high, and reducing the efficiency of the energy storage system. Utility Model Content
[0003] The utility model aims to provide a PCS temperature control component and an energy storage system which can adaptively control the temperature according to the PCS temperature.
[0004] In order to achieve the above purpose, the utility model adopts the following technical solutions:
[0005] The PCS temperature control component of the energy storage system includes: a second heat exchange structure arranged at the PCS; a first liquid cooling branch and a second liquid cooling branch respectively connected to the liquid inlet and the liquid outlet of the second heat exchange structure; a throttling device is arranged on the first liquid cooling branch, and the liquid inlet end of the first liquid cooling branch is connected to the second main liquid cooling pipeline; the liquid outlet end of the second liquid cooling branch is connected to the liquid return port of the liquid cooling unit; the second main liquid cooling pipeline is connected to the liquid outlet of the first heat exchange structure arranged at the energy storage medium, and the liquid outlet end of the second main liquid cooling pipeline is connected to the liquid return port of the liquid cooling unit; a third liquid cooling branch connected in parallel with the first liquid cooling branch, and a pipeline control valve is arranged on the third liquid cooling branch.
[0006] As described above, in the energy storage system PCS temperature control component, optionally, the pipeline control valve is a flow regulating valve.
[0007] As described above, in the energy storage system PCS temperature control component, optionally, the pipeline control valve is a non-regulatory electric switching valve.
[0008] As described above, the energy storage system PCS temperature control component, optionally, a temperature sensor is provided at the PCS, and the pipeline control valve is actuated according to the real-time temperature of the PCS detected by the temperature sensor.
[0009] The utility model also provides an energy storage system, including: a battery pack, a PCS, and a first heat exchange structure for exchanging heat with the battery pack, wherein the first heat exchange structure is connected to a liquid cooling unit via a first main liquid cooling pipeline and a second main liquid cooling pipeline, and the coolant flows from the liquid cooling unit to the first heat exchange structure via the first main liquid cooling pipeline, and flows back to the liquid cooling unit via the second main liquid cooling pipeline; and also includes the aforementioned energy storage system PCS temperature control component.
[0010] It can be seen from the above technical scheme that the utility model connects a bypass pipeline for regulating the PCS temperature to the liquid cooling pipeline after the energy storage medium of the energy storage system. The liquid inlet end of the bypass pipeline is connected in parallel with the first liquid cooling branch and the third liquid cooling branch. The flow of the first liquid cooling branch is relatively stable, which can ensure the minimum limit of the coolant required by the second heat exchange structure at the PCS, and ensure that the PCS can work normally. At the same time, a pipeline control valve is arranged on the third liquid cooling branch, which can control the on-off or flow of the third liquid cooling branch according to the real-time temperature at the PCS, so that the flow of the coolant entering the second heat exchange structure can be adaptively adjusted according to the temperature of the PCS, thereby ensuring that the PCS temperature does not exceed the maximum limit with the lowest refrigeration power consumption, and improving the efficiency of the entire system. BRIEF DESCRIPTION OF THE DRAWINGS
[0011] In order to more clearly illustrate the embodiments of the utility model, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0012] Figure 1 It is a schematic diagram of a PCS temperature control assembly according to an embodiment of the utility model;
[0013] Figure 2 This is a flow chart of a temperature control method according to one embodiment of the present invention;
[0014] Figure 3 The present invention is a flow chart of a temperature control method according to another embodiment of the present invention.
[0015] The specific implementation of the utility model is further described in detail below with reference to the accompanying drawings. DETAILED DESCRIPTION
[0016] The utility model is described in detail below in conjunction with the accompanying drawings. When describing the embodiments of the utility model in detail, for the convenience of explanation, the drawings representing the device structure will not be partially enlarged according to the general proportion, and the schematic diagram is only an example, which should not limit the scope of protection of the utility model. It should be noted that the drawings are simplified in form and use non-precise proportions, which are only used to facilitate and clearly assist in explaining the purpose of the embodiments of the utility model. At the same time, in the description of this application, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated; the terms "positive", "negative", "bottom", "upper", "lower", etc. indicate the orientation or position relationship based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the utility model.
[0017] In the description of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, it can also be the internal connection of two elements, it can be a wireless connection, or it can be a wired connection. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.
[0018] like Figure 1 As shown, the energy storage system of this embodiment includes an energy storage medium and a PCS for controlling the charging and discharging process of the energy storage medium and performing AC / DC conversion. The energy storage medium of this embodiment is a battery pack 1. In other embodiments, the energy storage medium may also be in the form of a battery cluster. The battery pack 1 is disposed in a cabinet, and the PCS and the battery pack 1 are electrically connected. For an energy storage system that adopts liquid cooling for heat dissipation, it also includes a first temperature control component for dissipating heat for the battery pack 1 (energy storage medium), and a second temperature control component for dissipating heat for the PCS.
[0019] The first temperature control component is an energy storage medium temperature control component, which is used to control the temperature of the battery pack 1. The first temperature control component includes a first main liquid cooling pipeline 10, a second main liquid cooling pipeline 11, and a first heat exchange structure (not shown) for heat exchange with the battery pack 1. The first heat exchange structure of this embodiment is a heat exchanger. The first main liquid cooling pipeline 10 and the second main liquid cooling pipeline 11 are respectively connected to the liquid cooling unit (not shown) and the first heat exchanger. The first main liquid cooling pipeline 10 is connected to the liquid outlet of the liquid cooling unit to realize the flow of coolant from the liquid cooling unit to the first heat exchanger at the battery pack 1. The liquid outlet of the second main liquid cooling pipeline 11 is connected to the liquid return port of the liquid cooling unit to realize the flow of coolant after heat exchange with the battery pack 1 back to the liquid cooling unit. In addition to the heat exchanger, in other embodiments, the heat exchange structure can also be a liquid storage structure such as a liquid storage tank or a liquid storage box. The coolant is passed into the liquid storage structure, and the battery pack is immersed in the coolant to directly exchange heat with the coolant.
[0020] The second temperature control component is a PCS temperature control component, which is used to control the temperature of the PCS. The second temperature control component includes a second heat exchange structure (not shown), a first liquid cooling branch 21, a second liquid cooling branch 22 and a third liquid cooling branch 23. The second heat exchange structure is arranged at the PCS, and is used to exchange heat with the PCS and control the temperature of the PCS, such as dissipating heat and cooling the PCS. The second heat exchange structure of this embodiment is also a heat exchanger. Similarly, the second heat exchange structure can also be a liquid storage structure, and the PCS is immersed in the coolant in the liquid storage structure for heat exchange. The following embodiments are described by taking the first and second heat exchange structures as heat exchangers as an example.
[0021] The first liquid cooling branch 21, the second liquid cooling branch 22 and the third liquid cooling branch 23 form a bypass branch passing through the second heat exchanger. The liquid inlet of the first liquid cooling branch 21 is connected to the second main liquid cooling pipeline 11, and the liquid outlet is connected to the liquid inlet of the second heat exchanger. The liquid inlet of the second liquid cooling branch 22 is connected to the liquid outlet of the second heat exchanger, and the liquid outlet is connected to the second main liquid cooling pipeline 11, and is connected to the liquid return port of the liquid cooling unit through the second main liquid cooling pipeline 11. A throttling device 24 is provided on the first liquid cooling branch 21. Along the flow direction of the coolant, the first liquid cooling branch 21 is located before the second liquid cooling branch 22, that is, the coolant first enters the first liquid cooling branch 21, passes through the second heat exchanger, and then enters the second liquid cooling branch 22. The third liquid cooling branch 23 and the first liquid cooling branch 21 are in parallel, the liquid outlet of the third liquid cooling branch 23 is connected to the liquid inlet of the second heat exchanger, and the liquid inlet is connected to the second main liquid cooling pipeline 11. A pipeline control valve 24 is provided on the third liquid cooling branch 23, and the pipeline control valve 24 is used to control the conduction or shutoff of the flow through the third liquid cooling branch 23, thereby adjusting the total amount of coolant entering the second heat exchanger. When the pipeline control valve 24 is a flow control valve, the flow of the third liquid cooling branch 23 can also be controlled.
[0022] The coolant flowing out of the first heat exchanger flows back to the liquid cooling unit through the second main liquid cooling pipeline 11. During the reflux process, when passing through the first liquid cooling branch 21 and the third liquid cooling branch 23, part of the coolant will flow into the second heat exchanger through the first liquid cooling branch 21, and then flow out of the second heat exchanger through the second liquid cooling branch 22, and return to the liquid cooling unit together with the coolant in the second main liquid cooling pipeline 11. In addition to entering the second heat exchanger through the first liquid cooling branch 21, when the third liquid cooling branch 23 is connected, part of the coolant can also enter the second heat exchanger through the third liquid cooling branch 23. The flow of coolant entering the second heat exchanger through the third liquid cooling branch 23 is adjusted according to the temperature of the PCS. For example, when the calorific value of the PCS is large and the temperature is high, the pipeline control valve 24 can be opened to allow more coolant to enter the second heat exchanger for heat exchange. On the contrary, when the calorific value of the PCS is small and the temperature is low, the pipeline control valve 24 can be closed to reduce the coolant entering the second heat exchanger. When the pipeline control valve 24 is a flow control valve, the total amount of coolant entering the second heat exchanger can be more accurately adjusted by changing the opening of the flow control valve.
[0023] The battery pack 1 in the energy storage system has a large calorific value and a high temperature requirement. Compared with the battery pack 1, the PCS has a relatively low calorific value and is more compatible with the temperature of the cooling medium. The utility model bypasses the liquid cooling branch connected to the PCS and connects it to the second main liquid cooling pipeline 11 after the battery pack 1. After the coolant flows out of the cooling unit, it first passes through the battery pack 1. After heat exchange at the first heat exchanger, a part of the coolant enters the second heat exchanger through the first liquid cooling branch 21 for heat exchange. When this part of the coolant flows through the first liquid cooling branch 21, it will first pass through the throttling device 24 for pressure reduction and temperature reduction, and then enter the second heat exchanger and PCS for heat exchange. No pipeline control valve is set on the first liquid cooling branch 21, and a fixed passage is maintained. The flux is set to the minimum flow limit when the third liquid cooling branch 23 is closed, which can always ensure that a certain amount of coolant enters the second heat exchanger, which can avoid the devastating effect of a single liquid cooling branch on the PCS when the valve fails, so that the PCS can always maintain operation at a lower power.
[0024] In addition, compared with the existing liquid-cooled energy storage system that bypasses the liquid cooling branch connected to the PCS and connects it to the first main liquid cooling pipeline 10 before the battery pack 1, the liquid cooling branch connected to the PCS is connected after the battery pack 1. Since the coolant passes through the battery pack 1 first, when the PCS temperature control component adjusts the flow, the battery pack 1 side will not be affected, and the battery pack 1 can still be cooled and dissipated in the form of full flow to ensure the stability of the battery pack operation. If it is connected to the first main liquid cooling pipeline, when the PCS side adjusts the flow, the flow on the battery pack 1 side will definitely change, affecting the temperature stability of the battery pack 1.
[0025] Combine the following Figure 2, the temperature control method of the PCS temperature control component of this embodiment is explained. In this embodiment, a temperature sensor is set at the PCS to detect the temperature of the PCS, so that the action of the pipeline control valve can be controlled according to the real-time temperature T of the PCS to adjust the flow rate of the coolant entering the second heat exchanger, thereby better improving the cooling efficiency and reducing energy consumption.
[0026] like Figure 2 As shown, the temperature control method of this embodiment includes the following steps:
[0027] S1. Detect the temperature of the PCS in real time to obtain the current temperature T of the PCS;
[0028] S2, when T ≥ the first temperature threshold T k When the pipeline control valve is opened, the first temperature threshold T k is the temperature value for opening the pipeline control valve, that is, the valve opening value of the pipeline control valve. When T<the second temperature threshold T g When the pipeline control valve is closed, the second temperature threshold T g It is the temperature value for closing the pipeline control valve, that is, the closing valve value of the pipeline control valve.
[0029] The pipeline control valve can be a flow control valve with adjustable opening, or a non-adjustable electric switch valve. It is preferred to use a flow control valve with adjustable flow, which can further subdivide the adjustment amount of the pipeline control valve according to the temperature change of the PCS, while ensuring the cooling effect of the PCS, reducing energy consumption and improving the efficiency of the entire system.
[0030] When the pipeline control valve is a flow control valve, as another implementation method, Figure 3 As shown, the temperature control method comprises the following steps:
[0031] S1', detect the temperature of the PCS in real time to obtain the current temperature T of the PCS, and calculate the temperature change rate ΔT every set time t (such as every 10 seconds), ΔT = (T-T') / t, T' represents the temperature obtained by the last detection, that is, the temperature t time ago, taking t = 10s as an example, T' is the temperature 10s ago;
[0032] S2', when T ≥ the first temperature threshold T k When the temperature changes, the flow control valve is opened, and the opening of the flow control valve is controlled according to the temperature change rate ΔT; in a specific application, when the flow control valve is opened, the initial opening of the flow control valve can be set to 20%;
[0033] S3', when T≥ temperature upper limit T max When T < lower limit of temperature T min When the flow control valve is closed, the lower limit of temperature Tmin Can be equal to the second temperature threshold T g .
[0034] Temperature upper limit T max and temperature lower limit T min are the highest and lowest temperature values when the PCS can maintain normal operation, and the first temperature threshold T k , the second temperature threshold T g , Temperature upper limit T max , Temperature lower limit T min , set time t, and the initial opening of the flow control valve are all empirical values, which are set according to the application scenarios of the energy storage system and different PCS products, and are not limited here.
[0035] Optionally, in step S2', this embodiment adjusts the opening of the flow control valve according to the temperature change rate. Adjusting the opening of the flow control valve according to the temperature change rate is more accurate than simply dividing the opening range of the flow control valve according to temperature. Specifically, this embodiment controls the opening of the flow control valve according to the following method:
[0036] When ΔT≥0.5℃, the flow control valve opening increases by 10% every time t;
[0037] When 0.5℃>ΔT≥0.3℃, the flow control valve opening increases by 5% every time t;
[0038] When 0.3℃>ΔT≥0.1℃, the flow control valve opening increases by 2% every time t;
[0039] When 0.1℃>ΔT≥-0.1℃, the flow control valve opening remains unchanged;
[0040] When -0.1℃>ΔT≥-0.3℃, the flow control valve opening decreases by 5% every time t;
[0041] When -0.3℃>ΔT, the flow control valve opening decreases by 10% every time t.
[0042] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. Energy storage system PCS temperature control component, characterized in that: include: A second heat exchange structure disposed at the PCS; A first liquid cooling branch and a second liquid cooling branch are respectively connected to the liquid inlet and the liquid outlet of the second heat exchange structure; a throttling device is provided on the first liquid cooling branch, and the liquid inlet end of the first liquid cooling branch is connected to the second main liquid cooling pipeline; the liquid outlet end of the second liquid cooling branch is connected to the liquid return port of the liquid cooling unit; the second main liquid cooling pipeline is connected to the liquid outlet of the first heat exchange structure arranged at the energy storage medium, and the liquid outlet end of the second main liquid cooling pipeline is connected to the liquid return port of the liquid cooling unit; A third liquid cooling branch is connected in parallel with the first liquid cooling branch, and a pipeline control valve is provided on the third liquid cooling branch.
2. The energy storage system PCS temperature control component according to claim 1, characterized in that: The pipeline control valve is a flow regulating valve.
3. The energy storage system PCS temperature control component according to claim 1, characterized in that: The pipeline control valve is a non-adjustable electric switching valve.
4. The energy storage system PCS temperature control component according to claim 1, characterized in that: The PCS is provided with a temperature sensor, and the pipeline control valve is actuated according to the real-time temperature of the PCS detected by the temperature sensor.
5. An energy storage system, characterized in that: include: The battery pack, the PCS, and the first heat exchange structure for exchanging heat between the battery pack, the first heat exchange structure being connected to the liquid cooling unit through a first main liquid cooling pipeline and a second main liquid cooling pipeline, the coolant flowing from the liquid cooling unit to the first heat exchange structure through the first main liquid cooling pipeline, and flowing back to the liquid cooling unit through the second main liquid cooling pipeline; It also includes an energy storage system PCS temperature control component as described in any one of claims 1-4.