A system for improving the electrical protection capability of a battery cluster

Abstract

This utility model discloses a system for improving the electrical protection capability of battery clusters, belonging to the field of battery cluster electrical protection technology. It solves the problem that traditional battery cluster electrical protection systems in the prior art are unable to effectively protect energy storage battery clusters. In this utility model, both ends of the in-cluster fuse are connected to the battery cluster. One end of the battery cluster is connected to the fuse inside the high-voltage box, one end of the fuse inside the high-voltage box is connected to a first contactor, and the other end of the battery cluster is connected to a second contactor. Both the first and second contactors are connected to a circuit breaker, which is connected to an overvoltage protection circuit. The battery cluster management unit is connected to the battery cluster via a Hall current sensor, and is also connected to the second contactor, the fuse inside the high-voltage box, and the first contactor. This utility model can be used to provide battery cluster protection circuits, configuring fuses inside the high-voltage box and in-cluster fuses, achieving regional dual short-circuit protection.

Description

Technical Field

[0001] This utility model relates to a system for improving the electrical protection capability of battery clusters, and belongs to the field of battery cluster electrical protection technology. Background Technology

[0002] With the large-scale construction of electrochemical energy storage power stations, lithium-ion battery energy storage systems have developed rapidly. The voltage levels of battery clusters have gradually increased, raising the difficulty of electrical protection. Currently, energy storage safety accidents occur frequently. Besides issues with the battery cells themselves, insufficient integrated electrical protection capabilities of energy storage systems are one of the main causes of these accidents.

[0003] Traditional short-circuit protection methods mainly rely on a single fuse. However, due to differences in the location of the short circuit and variations in the fuse manufacturing process, the fuse's breaking time may fluctuate significantly, resulting in unstable protection performance. Furthermore, in extreme cases, a single fuse may fail to interrupt the short-circuit current in time, thus failing to effectively protect the energy storage battery cluster.

[0004] In conclusion, a system is needed to improve the electrical protection capabilities of battery clusters. Utility Model Content

[0005] A brief overview of the present invention is given below to provide a basic understanding of certain aspects thereof. It should be understood that this overview is not an exhaustive summary of the present invention. It is not intended to identify key or essential parts of the present invention, nor is it intended to limit the scope of the present invention. Its purpose is merely to present certain concepts in a simplified form as a prelude to the more detailed description that follows.

[0006] In view of this, in order to solve the problem that traditional battery cluster electrical protection systems in the prior art are unable to effectively protect energy storage battery clusters, this utility model provides a system to improve the electrical protection capability of battery clusters.

[0007] The technical solution is as follows: A system for improving the electrical protection capability of battery clusters, including a battery cluster management unit, an overvoltage protection circuit, a Hall current sensor, a fuse inside the high-voltage box, a fuse inside the cluster, a circuit breaker, a first contactor, and a second contactor;

[0008] Both ends of the fuse in the cluster are connected to the battery cluster. One end of the battery cluster is connected to the fuse in the high-voltage box. One end of the fuse in the high-voltage box is connected to the first contactor. The other end of the battery cluster is connected to the second contactor. Both the first and second contactors are connected to the circuit breaker. The circuit breaker is connected to the overvoltage protection circuit.

[0009] The battery cluster management unit is connected to one end of the battery cluster via a Hall current sensor, one end of the battery cluster management unit is connected to one end of the second contactor, one end of the battery cluster management unit is connected to one end of the fuse in the high-voltage box, and one end of the battery cluster management unit is connected to one end of the first contactor.

[0010] Furthermore, the overvoltage protection circuit includes a first lightning protection fuse, a surge protector, and a second lightning protection fuse connected in sequence.

[0011] The beneficial effects of this utility model are as follows: This utility model uses two fuses of the same specification, namely the fuse inside the high-voltage box and the fuse inside the battery pack, which are installed in different positions inside the battery pack to realize regional protection of the energy storage system; when the short-circuit current inside the pack is the same and a short circuit occurs in different battery packs, the fuse closer to the short-circuit point will blow before the other fuse; when an external short circuit occurs, the fuse inside the high-voltage box will blow first, and according to the different short-circuit locations inside the energy storage battery pack, the short-circuit current can be cut off more quickly. Attached Figure Description

[0012] The accompanying drawings, which are included to provide a further understanding of the present invention and constitute a part of this invention, illustrate exemplary embodiments of the present invention and, together with the description thereof, serve to explain the present invention and do not constitute an undue limitation thereof. In the drawings:

[0013] Figure 1 A schematic diagram of a system for improving the electrical protection capability of battery clusters;

[0014] Figure 2 This is a schematic diagram of the internal circuit structure of the high-voltage box.

[0015] Reference numerals: 1. Battery cluster management unit; 2. Overvoltage protection circuit; 3. Battery cluster; 4. Hall current sensor; 5. Surge protector; FU1. Fuse inside high voltage box; FU2. Fuse inside cluster; QF. Circuit breaker; 1FU1. First lightning protection fuse; 2FU2. Second lightning protection fuse. Detailed Implementation

[0016] To make the embodiments and advantages of this utility model clearer, the embodiments of this utility model will be described in further detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not an exhaustive list of all embodiments. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of this utility model can be combined with each other.

[0017] In this utility model, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed 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 connection of two electrical components or the interaction between two electrical components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0018] refer to Figure 1 and Figure 2 This embodiment describes a system for enhancing the electrical protection capabilities of a battery cluster, comprising a battery cluster management unit 1, an overvoltage protection circuit 2, a Hall current sensor 4, a high-voltage box fuse FU1, a cluster fuse FU2, a circuit breaker QF, a first contactor KM1, and a second contactor KM2.

[0019] Both ends of the in-cell fuse FU2 are connected to the battery cluster 3. One end of the battery cluster 3 is connected to the in-voltage box fuse FU1. One end of the in-voltage box fuse FU1 is connected to the first contactor KM1. The other end of the battery cluster 3 is connected to the second contactor KM2. Both the first contactor KM1 and the second contactor KM2 are connected to the circuit breaker QF. The circuit breaker QF is connected to the overvoltage protection circuit 2.

[0020] The battery cluster management unit 1 is connected to one end of the battery cluster 3 via the Hall current sensor 4, and there is a current. The battery cluster management unit 1 is connected to one end of the second contactor KM2, and there is a voltage V-. The battery cluster management unit 1 is connected to one end of the fuse FU1 in the high voltage box, and there is a voltage V1+. The battery cluster management unit 1 is connected to one end of the first contactor KM1, and there is a voltage V2+.

[0021] Specifically, during system operation, the battery cluster sampling circuit (voltage sampling, current sampling, etc.) is prone to breakdown and short circuit. Conventional circuit breakers, contactors, and fuses are configured in the high-voltage box to provide disconnection and protection for the energy storage battery cluster. However, when a short circuit occurs, the fuse blows and the contactor sticks, which are not easy to maintain and replacement will increase costs. Therefore, it is necessary to carry out protection design for the sampling circuit in the high-voltage box to prevent short circuits from occurring.

[0022] Regarding voltage sampling, the high-voltage box sampling harness uses a rated operating voltage that meets the battery cluster voltage level, and is protected by a high-voltage resistant fiberglass tube, effectively preventing short circuits caused by grounding of the positive and negative terminals through the sampling harness. Inside the high-voltage box, the operating voltage between the positive and negative terminals of the BCU voltage sampling port connector should be greater than the maximum operating voltage of the battery cluster. Since the operating voltage between conventional connector pins does not meet this requirement, a pin-separated design is used, with the number of spaced pins determined based on the battery cluster voltage level and the connector operating voltage level. Regarding current sampling, when using a shunt to sample the battery cluster current, the current sampling port is also prone to short circuits. Using a Hall effect current sensor (4-sampling unit) can achieve isolation and prevent short circuits.

[0023] refer to Figure 2 ①, ②, and ③ are the battery cluster voltage acquisition harnesses, which are high-voltage silicone harnesses. The rated operating voltage meets the maximum operating voltage of battery cluster 3. The sampling harnesses are protected by fiberglass tubes of DC 7000V or higher to enhance the voltage resistance of the sampling harnesses. ④ is the current sampling harness. The Hall current sensor 4 and the battery cluster management unit 1 communicate to transmit the battery cluster current magnitude, realize current sampling isolation, and improve electrical protection capability. B+ and B- represent the two poles of battery cluster 3.

[0024] Furthermore, the overvoltage protection circuit 2 includes a first lightning protection fuse 1FU1, a surge protector 5, and a second lightning protection fuse 2FU2 connected in sequence.

[0025] Specifically, to enhance the overvoltage protection capability of the energy storage battery cluster, a surge protector 5 is added between the P+ and P- outlets of the high-voltage box, and a lightning protection fuse is configured to improve the overvoltage protection capability of the battery cluster 3. Simultaneously, the surge protector failure signal and the lightning protection fuse blown signal are connected to the battery cluster management unit 1 to prevent overvoltage protection from failing due to surge protector failure.

[0026] The working principle of a system to improve the electrical protection capability of battery clusters is as follows: As the core of short-circuit protection for energy storage battery clusters, the fuse can promptly cut off the short-circuit current when the energy storage system is short-circuited, protecting the safety of the energy storage battery cluster. Due to the influence of the short-circuit point location and the differences in fuse manufacturing, the melting time of the fuse also varies. If the fuse cannot cut off the short-circuit current in time, the energy storage battery will experience thermal runaway, which may lead to a fire. In addition to the fuse FU1 configured in the high-voltage box, an in-cluster fuse FU2 is added in the energy storage battery cluster to provide dual short-circuit protection in different areas. Adding fuses in the cluster can achieve wider area short-circuit protection, effectively improving the reliability of fuse protection and better enhancing the short-circuit protection capability of the energy storage battery cluster.

[0027] When the short circuit point occurs within battery cluster 3, the fuse FU2 within the cluster is closer to the short circuit point than the fuse FU1 in the high-voltage box, and will blow before the fuse FU1 in the high-voltage box. When an external short circuit occurs or when the short circuit occurs within a cluster other than battery cluster 3, the fuse FU1 in the high-voltage box is closer to the short circuit point. At this time, the short circuit current is cut off by the protection of FU1.

[0028] Although the present invention has been described with reference to a limited number of embodiments, those skilled in the art will understand from the foregoing description that other embodiments are conceivable within the scope of the present invention described herein. Furthermore, it should be noted that the language used in this specification has been chosen primarily for readability and edibility purposes, and not for interpreting or limiting the subject matter of the invention. Therefore, many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the appended claims. Regarding the scope of the invention, the disclosure made is illustrative and not restrictive, and the scope of the invention is defined by the appended claims.

Claims

1. A system for improving the electrical protection capability of battery clusters, characterized in that, It includes a battery cluster management unit (1), an overvoltage protection circuit (2), a Hall current sensor (4), a high-voltage box fuse (FU1), a cluster fuse (FU2), a circuit breaker (QF), a first contactor (KM1), and a second contactor (KM2). Both ends of the in-cell fuse (FU2) are connected to the battery cluster (3). One end of the battery cluster (3) is connected to the in-voltage box fuse (FU1). One end of the in-voltage box fuse (FU1) is connected to the first contactor (KM1). The other end of the battery cluster (3) is connected to the second contactor (KM2). Both the first contactor (KM1) and the second contactor (KM2) are connected to the circuit breaker (QF). The circuit breaker (QF) is connected to the overvoltage protection circuit (2). The battery cluster management unit (1) is connected to one end of the battery cluster (3) via a Hall current sensor (4), the battery cluster management unit (1) is connected to one end of the second contactor (KM2), the battery cluster management unit (1) is connected to one end of the fuse (FU1) in the high voltage box, and the battery cluster management unit (1) is connected to one end of the first contactor (KM1). The overvoltage protection circuit (2) includes a first lightning protection fuse (1FU1), a surge protector (5), and a second lightning protection fuse (2FU2) connected in sequence.

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