A kind of energy storage system buck pre-charging circuit and energy storage battery system

Abstract

The utility model discloses a kind of energy storage system Buck pre-charging circuit and energy storage battery system, comprising: battery pack, discharge switch module, charging switch module, pre-discharge circuit and inverter subsystem;The negative terminal of the battery pack is connected with the S pole of the switch tube Q2 of the discharge switch module, and the negative terminal of the battery pack is connected with the first end of the pre-discharge circuit;The positive terminal of the battery pack is connected with the second end of the pre-discharge circuit, and the positive terminal of the battery pack is connected with the positive terminal of the inverter subsystem;The D pole of the switch tube Q2 of the discharge switch module is connected with the D pole of the switch tube Q3 of the charging switch module, and the D pole of the switch tube Q3 of the charging switch module is connected with the third end of the pre-discharge circuit, and the S pole of the switch tube Q3 of the charging switch module is connected with the negative terminal of the inverter subsystem.The scheme of the application can improve the efficiency of circuit pre-charging, and significantly improve the stability of circuit in pre-charging link.

Description

Technical Field

[0001] This utility model relates to the field of energy storage battery systems, and in particular to a Buck pre-charging circuit for an energy storage system and an energy storage battery system. Background Technology

[0002] In recent years, energy issues have become a major concern for countries worldwide, particularly energy storage, a crucial aspect that is unavoidable for both businesses and residents. Among these, the storage and supply of electrical energy is of paramount importance. Given this industrial environment, solar power generation and energy storage are booming, especially in Europe, America, and Africa, where the demand for energy storage battery systems is particularly urgent.

[0003] Existing Buck pre-charge circuits struggle to balance size and power; either they are too large, occupying excessive space on the BMS board, or they are too small, resulting in excessively long pre-charge times. Furthermore, many current energy storage batteries support inverters from different brands, and the corresponding capacitor capacities vary between these brands. This introduces uncertainty into the energy required for battery startup, further increasing the demands on the pre-charge circuit. Therefore, this application provides a Buck pre-charge circuit for an energy storage system that effectively solves the above problems. Utility Model Content

[0004] The technical problem to be solved by this utility model is: how to design a solution that can improve the efficiency of circuit pre-charging and significantly improve the stability of the circuit in the pre-charging stage.

[0005] In a first aspect, this application proposes a Buck pre-charging circuit for an energy storage system. The circuit includes: a battery pack, a discharge switch module, a charging switch module, a pre-discharge circuit, and an inverter subsystem. The negative terminal of the battery pack is connected to the source (S) terminal of the switching transistor Q2 of the discharge switch module, and the negative terminal of the battery pack is connected to the first terminal of the pre-discharge circuit. The positive terminal of the battery pack is connected to the second terminal of the pre-discharge circuit, and the positive terminal of the battery pack is connected to the positive terminal of the inverter subsystem. The drain (D) terminal of the switching transistor Q2 of the discharge switch module is connected to the drain (D) terminal of the switching transistor Q3 of the charging switch module, the drain (D) terminal of the switching transistor Q3 of the charging switch module is connected to the third terminal of the pre-discharge circuit, and the source (S) terminal of the switching transistor Q3 of the charging switch module is connected to the negative terminal of the inverter subsystem.

[0006] A further technical solution is that the inverter subsystem includes an interconnected capacitor C1 and a DC / AC module, the pre-discharge circuit includes a switch Q4 and a capacitor C2; the positive terminal of the battery pack is connected to the positive terminal of the capacitor C1, the source terminal of the switch Q3 of the charging switch module is connected to the negative terminal of the capacitor C1, and the source terminal of the switch Q4 is connected to the positive terminal of the capacitor C1 through the capacitor C2.

[0007] A further technical solution is that the pre-discharge circuit also includes an inductor L9, a resistor R9, and a thermistor module NTC1. The drain of the switching transistor Q4 is connected to the negative terminal of the capacitor C1 in sequence through the inductor L9, the resistor R9, and the thermistor module NTC1.

[0008] A further technical solution is that the pre-discharge circuit also includes a capacitor C3, and the source terminal of the switching transistor Q4 is connected to the thermistor module NTC1 in sequence through capacitors C2 and C3.

[0009] Furthermore, the first terminal of the pre-discharge circuit corresponds to the source (S) terminal of the switching transistor Q4; further, the second terminal of the pre-discharge circuit corresponds to the end of the capacitor C2 furthest from the switching transistor Q4; further, the third terminal of the pre-discharge circuit corresponds to the end of the capacitor C3 closest to the thermistor module NTC1.

[0010] Secondly, this application proposes an energy storage battery system, which includes the energy storage system Buck pre-charging circuit as described in the first aspect; compared with the prior art, the energy storage battery system has achieved significant improvements in the efficiency of circuit pre-charging and the stability of the pre-charging process.

[0011] In summary, existing Buck pre-charging circuits struggle to balance size and power. They are either too large, occupying excessive space on the BMS board, or too small, resulting in excessively long pre-charging times. Furthermore, many energy storage batteries support inverters from different brands, and the capacitor capacities for batteries vary between these brands. This introduces uncertainty into the energy required for battery startup, further increasing the demands on the pre-charging circuit. Therefore, this application proposes a Buck pre-charging circuit and energy storage battery system that improves the efficiency of circuit pre-charging and significantly enhances the stability of the circuit during the pre-charging phase. Attached Figure Description

[0012] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0013] Figure 1 This is an overall schematic diagram of the Buck pre-charging circuit of the energy storage system proposed in this utility model.

[0014] Figure 2 This is another overall schematic diagram of the Buck pre-charging circuit of the energy storage system proposed in this utility model.

[0015] Figure 3 This is a pre-discharge circuit diagram of the Buck pre-charge circuit of the energy storage system proposed in this utility model. Detailed Implementation

[0016] The technical solutions in the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Similar component reference numerals in the drawings represent similar components. Obviously, the embodiments described below are only some embodiments of this utility model, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model.

[0017] It should be understood that the terminology used in this specification of embodiments of the present invention is for the purpose of describing particular embodiments only and is not intended to limit the embodiments of the present invention. As used in this specification of embodiments of the present invention and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0018] Example See Figures 1 to 3 The diagram shows a Buck pre-charging circuit for an energy storage system according to an embodiment of this utility model. See details below. Figure 1The circuit includes: a battery pack, a discharge switch module, a charging switch module, a pre-discharge circuit, and an inverter subsystem. The negative terminal of the battery pack is connected to the source (S) terminal of the switching transistor Q2 of the discharge switch module, and the negative terminal of the battery pack is connected to the first terminal of the pre-discharge circuit. The positive terminal of the battery pack is connected to the second terminal of the pre-discharge circuit, and the positive terminal of the battery pack is connected to the positive terminal of the inverter subsystem. The drain (D) terminal of the switching transistor Q2 of the discharge switch module is connected to the drain (D) terminal of the switching transistor Q3 of the charging switch module, the drain (D) terminal of the switching transistor Q3 of the charging switch module is connected to the third terminal of the pre-discharge circuit, and the source (S) terminal of the switching transistor Q3 of the charging switch module is connected to the negative terminal of the inverter subsystem. For details, see the above scheme. Figure 2 As shown, the battery pack, discharge switch module, charging switch module, pre-discharge circuit, and inverter subsystem are numbered 1 to 5 in sequence. The positive terminal of the battery pack is directly connected to the pre-discharge circuit through a vertical gray line.

[0019] In one embodiment, the inverter subsystem includes a capacitor C1 and a DC / AC module connected to each other, and the pre-discharge circuit includes a switch Q4 and a capacitor C2; the positive terminal of the battery pack is connected to the positive terminal of the capacitor C1, the source terminal of the switch Q3 of the charging switch module is connected to the negative terminal of the capacitor C1, and the source terminal of the switch Q4 is connected to the positive terminal of the capacitor C1 through the capacitor C2.

[0020] In one embodiment, the pre-discharge circuit further includes an inductor L9, a resistor R9, and a thermistor module NTC1. The drain of the switching transistor Q4 is connected to the negative terminal of the capacitor C1 in sequence through the inductor L9, the resistor R9, and the thermistor module NTC1.

[0021] In one embodiment, the pre-discharge circuit further includes capacitor C3, and the source terminal of the switching transistor Q4 is connected to the thermistor module NTC1 in sequence through capacitors C2 and C3.

[0022] In one embodiment, the first terminal of the pre-discharge circuit corresponds to the source (S) terminal of the switching transistor Q4; further, the second terminal of the pre-discharge circuit corresponds to the end of the capacitor C2 furthest from the switching transistor Q4; further, the third terminal of the pre-discharge circuit corresponds to the end of the capacitor C3 closest to the thermistor module NTC1.

[0023] In one embodiment, this application proposes an energy storage battery system, which includes a Buck pre-charging circuit as described in any of the above embodiments. In the Buck pre-charging circuit, switch Q4 has a soft-start function. Capacitor C4, resistor R7, and TVS1 are noise and spike voltage suppression devices for switch Q4. R10 is the driving resistor for switch Q4. L9 is a freewheeling inductor and a current sampling resistor. Thermistor module NTC1 is used to suppress inrush current. The cathode of D1 is connected to the positive terminal B1 of the battery pack; the drain terminal of switch Q4 is connected to the negative terminal B- of the battery pack; and the output terminal of thermistor module NTC1 is connected to the common point between switches Q2 and Q3. Further, the source terminal of switch Q4 is connected to one end of L9, the other end of L9 is connected to the sampling resistor R9, and the other end of R9 is connected to one end of the thermistor module NTC1. Furthermore, the switching transistor Q4 precharges the C1 capacitor in the inverter subsystem by pulse switching. The switching pulse frequency can be set, and the current can be adjusted. Compared with traditional circuits, the Buck pre-charging circuit has the characteristics of large pre-charging current and strong pre-charging capability. Therefore, in actual operation, there is no need to worry about insufficient pre-charging power leading to failure to pre-charge, nor is there any need to worry about the pre-charging resistor overheating and being damaged.

[0024] In summary, existing Buck pre-charging circuits struggle to balance size and power, either being too large and taking up too much space on the BMS board, or having too low power and resulting in excessively long pre-charging times. Therefore, this application proposes a Buck pre-charging circuit and a battery system for an energy storage system, which can improve the efficiency of circuit pre-charging and significantly enhance the stability of the circuit during the pre-charging phase.

[0025] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0026] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0027] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0028] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0029] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. The illustrative expressions of the above terms in this specification should not be construed as necessarily referring to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0030] Obviously, those skilled in the art can make various modifications and variations to this utility model without departing from its spirit and scope. Since these modifications and variations fall within the scope of the claims of this utility model and their equivalents, this utility model also intends to include these modifications and variations.

[0031] The above description describes specific embodiments of this utility model, but the scope of protection of this utility model is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this utility model, and these modifications or substitutions should all be covered within the scope of protection of this utility model. Therefore, the scope of protection of this utility model should be determined by the scope of the claims.

Claims

1. A Buck pre-charging circuit for an energy storage system, characterized in that, The circuit includes: The system comprises a battery pack, a discharge switch module, a charging switch module, a pre-discharge circuit, and an inverter subsystem. The negative terminal of the battery pack is connected to the source (S) terminal of the switching transistor Q2 of the discharge switch module, and the negative terminal of the battery pack is connected to the first terminal of the pre-discharge circuit. The positive terminal of the battery pack is connected to the second terminal of the pre-discharge circuit, and the positive terminal of the battery pack is connected to the positive terminal of the inverter subsystem. The drain (D) terminal of the switching transistor Q2 of the discharge switch module is connected to the drain (D) terminal of the switching transistor Q3 of the charging switch module, the drain (D) terminal of the switching transistor Q3 of the charging switch module is connected to the third terminal of the pre-discharge circuit, and the source (S) terminal of the switching transistor Q3 of the charging switch module is connected to the negative terminal of the inverter subsystem.

2. The Buck pre-charging circuit of the energy storage system according to claim 1, characterized in that: The inverter subsystem includes an interconnected capacitor C1 and a DC / AC module. The pre-discharge circuit includes a switch Q4 and a capacitor C2. The positive terminal of the battery pack is connected to the positive terminal of the capacitor C1. The source terminal of the switch Q3 of the charging switch module is connected to the negative terminal of the capacitor C1. The source terminal of the switch Q4 is connected to the positive terminal of the capacitor C1 through the capacitor C2.

3. The Buck pre-charging circuit of the energy storage system according to claim 2, characterized in that: The pre-discharge circuit also includes an inductor L9, a resistor R9, and a thermistor module NTC1. The drain of the switching transistor Q4 is connected to the negative terminal of the capacitor C1 in sequence through the inductor L9, the resistor R9, and the thermistor module NTC1.

4. The Buck pre-charging circuit of the energy storage system according to claim 3, characterized in that: The pre-discharge circuit also includes capacitor C3, and the source terminal of the switching transistor Q4 is connected to the thermistor module NTC1 in sequence through capacitors C2 and C3.

5. The Buck pre-charging circuit of the energy storage system according to claim 4, characterized in that: The first terminal of the pre-discharge circuit corresponds to the source (S) terminal of the switching transistor Q4.

6. The Buck pre-charging circuit of the energy storage system according to claim 5, characterized in that: The second terminal of the pre-discharge circuit corresponds to the terminal of capacitor C2 furthest from switch Q4.

7. The Buck pre-charging circuit of the energy storage system according to claim 6, characterized in that: The third terminal of the pre-discharge circuit corresponds to the end of capacitor C3 that is close to the thermistor module NTC1.

8. An energy storage battery system, characterized in that, The energy storage battery system includes the energy storage system Buck precharge circuit as described in any one of claims 1 to 7.

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