Battery disconnect unit

Abstract

This utility model relates to a battery disconnection unit for transferring battery power to or disconnecting battery power from a load. The battery disconnection unit according to this utility model includes: a first main relay connected between the positive terminal of the battery and the positive terminal of the inverter; a second main relay connected between the negative terminal of the battery and the negative terminal of the inverter; a pre-charge relay connected in parallel with the first main relay for initial charging of a DC link capacitor connected in parallel with the inverter; and a control unit including one or more processors and a memory, wherein the control unit controls the connection or disconnection of the first main relay, the second main relay, and the pre-charge relay. The first main relay and the pre-charge relay are composed of relays of different types, thereby having the advantage of improving the reliability of the battery disconnection unit.

Description

Technical Field

[0001] This utility model relates to a battery disconnection unit for connecting or disconnecting the power supply and load of a battery, and more particularly to a battery disconnection unit using a semiconductor relay. Background Technology

[0002] In the field of environmentally friendly (electric, hydrogen-powered, hybrid) vehicles and e-mobility, technologies that safely supply power to or disconnect the battery from the motor are crucial for providing safety and stability.

[0003] Therefore, a battery pack system can consist of a battery module assembly (BMA), a battery management unit (BMU), a cell monitoring unit (CMU), and a battery disconnect unit (BDU).

[0004] The battery disconnection unit is located between the inverter of the battery and the motor, and serves to supply power from the battery to the motor or disconnect power from the battery.

[0005] The battery disconnect unit uses a mechanical relay to supply or disconnect power, but mechanical relays have disadvantages such as short lifespan, generating operating noise, and being relatively large and heavy.

[0006] In addition, if a mechanical relay melts due to overcurrent or other reasons, it will be unable to disconnect the overcurrent from the battery. As a result, loads such as inverters or motors connected to the battery may also be damaged, or there may be a risk of fire.

[0007] To prevent this, a mechanical relay with an electronic fuse (e-fuse) is proposed, in which a sensor is installed on the line connected to the mechanical relay and the mechanical relay is disconnected when an overcurrent flows.

[0008] However, even with the addition of a separate sensor, the following problem remains: sensing current values ​​to detect overcurrent may cause damage due to the overcurrent flowing during the delay before the relay is disconnected.

[0009] The inventors of this invention have been dedicated to researching and solving the problems of battery disconnection units using existing mechanical relays. After extensive efforts, this invention was finally completed, providing a battery disconnection unit that improves fault response capability and stability by combining a mechanical relay using an electronic fuse and a semiconductor relay. Utility Model Content

[0010] The technical problem to be solved

[0011] The purpose of this invention is to provide a battery disconnection unit that further improves reliability by using an electronic relay (which simultaneously uses a mechanical relay and a semiconductor) in the battery disconnection unit.

[0012] In addition, another objective of this invention is to provide a battery disconnection unit that can more flexibly handle faults by using relays of different types in the battery disconnection unit.

[0013] On the other hand, other objectives not explicitly stated in this invention can be further considered within the scope of what can be readily inferred from the following detailed description and its effects.

[0014] Technical solutions for solving the problem

[0015] The battery disconnection unit according to this utility model includes: a first main relay connected between the positive terminal of the battery and the positive terminal of the inverter; a second main relay connected between the negative terminal of the battery and the negative terminal of the inverter; a pre-charge relay connected in parallel with the first main relay to perform initial charging of the DC link capacitor connected in parallel with the inverter; and a control unit including one or more processors and a memory, wherein the control unit controls the connection or disconnection of the first main relay, the second main relay and the pre-charge relay; the first main relay and the pre-charge relay are composed of relays of different types from each other.

[0016] The first main relay is an electronic fuse relay, which includes a mechanical relay and a sensor for sensing the voltage or current between the battery and the inverter. The control unit connects or disconnects the mechanical relay based on the voltage or current measured by the sensor.

[0017] The second main relay is composed of a relay of a different type than the first main relay.

[0018] When the first main relay is a semiconductor relay, the second main relay is an electronic fuse relay. The electronic fuse relay includes a mechanical relay and a sensor for sensing the voltage or current between the battery and the inverter. The control unit connects or disconnects the mechanical relay based on the voltage or current measured by the sensor.

[0019] The precharge relay is a semiconductor relay.

[0020] When the first main relay fails, the precharge relay acts as the main relay connecting the positive terminal of the battery and the positive terminal of the inverter.

[0021] The battery disconnection unit also includes a pre-charge resistor connected between the pre-charge relay and the positive terminal of the inverter.

[0022] The second main relay is a structure in which a mechanical relay and a semiconductor relay are connected in parallel.

[0023] The semiconductor relay is a back-to-back structure consisting of a pair of semiconductor switches connected in opposite directions of energization.

[0024] Technical effect

[0025] According to this invention, by combining electronic fuse mechanical relays and semiconductor relays in the battery disconnection unit, the stability of the battery disconnection unit can be further improved.

[0026] In addition, by using relays of different types, there is an advantage that relay failures will not occur simultaneously.

[0027] On the other hand, even effects not explicitly mentioned herein, as long as they are contemplated by the technical features of this utility model, should be regarded as described in the following specification and their potential effects. Attached Figure Description

[0028] Figure 1 This is a schematic structural diagram of a battery disconnection unit according to any preferred embodiment of the present invention.

[0029] Figure 2 This is a schematic structural diagram of the control unit of the battery disconnection unit in any preferred embodiment of the present invention.

[0030] Figure 3 This is a schematic structural diagram of a battery system including a battery disconnection unit, which is a preferred embodiment of the present invention.

[0031] Figure 4 This is a schematic structural diagram of the semiconductor relay included in the battery disconnection unit of any preferred embodiment of the present invention.

[0032] Figure 5 This is a schematic structural diagram of the battery system included in the battery disconnection unit of another preferred embodiment of the present invention.

[0033] Figure 6 This is a schematic structural diagram of the relay included in the battery disconnection unit of another preferred embodiment of the present invention.

[0034] The accompanying drawings are provided as examples to help understand the technical concept of this utility model and do not limit the scope of this utility model. Detailed Implementation

[0035] Hereinafter, with reference to the accompanying drawings, the structure of the present invention according to various embodiments and the effects produced by the structure will be studied. In describing the present invention, detailed descriptions will be omitted if it is determined that relevant known functions are obvious to those skilled in the art and may unnecessarily obscure the subject matter of the present invention.

[0036] The terms "first," "second," etc., can be used to describe various constituent elements, but the constituent elements are not limited to the terms used above. These terms are used only to distinguish one constituent element from others. For example, without departing from the scope of the present invention, "first constituent element" can be named "second constituent element," and similarly, "second constituent element" can be named "first constituent element." Furthermore, unless the context clearly specifies otherwise, singular expressions include plural expressions. Unless otherwise defined, the terms used in the embodiments of the present invention should be interpreted as having the meaning commonly understood by those skilled in the art.

[0037] Hereinafter, with reference to the accompanying drawings, the structure of the present invention according to various embodiments and the effects produced by the structure will be studied.

[0038] Figure 1 This is a schematic structural diagram of a battery disconnection unit according to any preferred embodiment of the present invention.

[0039] The battery disconnection unit 10 may include a first main relay 11, a second main relay 12, a precharge relay 13, and a control unit 14.

[0040] The first main relay 11 is connected between the positive terminal of the battery 5 and the positive terminal of the DC link capacitor 3 to supply power to or disconnect the inverter 2.

[0041] The second main relay 12 is connected between the negative terminal of the battery 5 and the negative terminal of the DC link capacitor 3, so as to supply power to or disconnect power to the inverter 2 together with the first main relay 11.

[0042] The pre-charge relay 13 and the pre-charge resistor 16 are connected in parallel with the first main relay 11 and are used to initially charge the DC link capacitor 3.

[0043] The pre-charge relay 13 supplies the voltage limited by the pre-charge resistor 16 to the DC link capacitor 3 and the inverter 2 to prevent damage to the motor 1 due to the inrush current during initial startup. After the voltage of the DC link capacitor 3 reaches a certain voltage, it switches to the off state so that the power of the battery 5 can be supplied to the inverter 2 through the first main relay 11.

[0044] The control unit 14 receives instructions from the battery management unit or uses current or voltage information measured by the sensor 15 to control the relay.

[0045] Therefore, the control unit 14 may include more than one processor and memory.

[0046] Figure 2 This is a schematic structural diagram of the control unit included in any preferred embodiment of the present invention's battery disconnection unit.

[0047] The control unit 14 may include one or more processors 141 and memory 142.

[0048] The memory 142 may store instructions, data structures, and program code that can be read by the processor 141. In this embodiment, at least the actions performed by the processor 141 can be achieved by executing the instructions or code of the program stored in the memory.

[0049] The memory may include flash memory type, hard disk type, multimedia card micro type, card type memory (e.g., SD or XD memory), and may include: non-volatile memory, including at least one of read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), programmable read-only memory (PROM), magnetic storage, magnetic disk and optical disk; and volatile memory, such as random access memory (RAM) or static random access memory (SRAM).

[0050] The memory 142 can store more than one instruction or program, which can be used when the processor 141 controls the relays 11, 12, 13 or to send and receive data through the communication unit (not shown).

[0051] The processor 141 controls the overall operation of the battery disconnection unit 10. For example, the processor 141 can control the overall operation of the battery disconnection unit 10, such as supplying or disconnecting power to the battery, by executing one or more instructions stored in the memory 142.

[0052] For example, processor 141 may be composed of at least one of the following: a central processing unit, a microprocessor, a graphics processing unit, application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), an application processor, a neural network processing unit, or an AI-specific processor with a hardware architecture specifically designed for processing AI models, but not limited to these.

[0053] Figure 3 An example of a battery system including a battery disconnection unit, showing a preferred embodiment of the present invention.

[0054] The battery system may include: an inverter 2 for driving a motor 1; a battery 5 for supplying power to the motor 1; a cell monitoring unit (CMU) 6 for monitoring the cells of the battery 5; a battery management unit (BMU) 4 for managing the battery system; and a battery disconnection unit 10 for managing the connection between the battery 5 and the motor 1.

[0055] The first main relay 11 and the precharge relay 13 of the battery disconnection unit 10 can be composed of relays of different types from each other.

[0056] For example, when the first main relay 11 is a mechanical relay, the precharge relay 13 can be made of a semiconductor relay; conversely, when the first main relay 11 is a semiconductor relay, the precharge relay 13 can be made of a mechanical relay.

[0057] By configuring the first main relay 11 and the precharge relay 13 as different types of relays, the reliability of the battery disconnection unit 10 can be improved. This is because when they are composed of the same type of relays, the probability of simultaneous failure under similar conditions may increase.

[0058] When the first main relay 11 is a mechanical relay, the first main relay 11 can be an electronic fuse relay that controls the connection or disconnection based on the measurement value of the sensor 15.

[0059] Ordinary thermal fuses are designed to disconnect by causing an overcurrent to raise the temperature. However, even if an overcurrent flows, the fuse does not disconnect immediately, thus limiting its ability to protect circuits or components.

[0060] Electronic fuses are used to compensate for the shortcomings of thermal fuses. The sensor 15 senses the current or voltage. When a high voltage or high current flows through the circuit, which is higher than the designed voltage or current, the control unit 14 can determine it and disconnect the first main relay 11 or the second main relay 12.

[0061] When the first main relay 11 is such a mechanical relay, the precharge relay 13 can be composed of an electronic semiconductor relay of a different type from the mechanical relay.

[0062] When the precharge relay 13 is composed of a semiconductor relay, the precharge relay 13 can be a MOSFET (Si, SiC, IGBT, etc.) used to implement a bidirectional electronic relay.

[0063] Figure 4 This is a schematic structural diagram of a semiconductor relay according to any preferred embodiment of the present invention.

[0064] A MOSFET is a structure that includes a diode to block the flow of current when the switch is off. Therefore, in the case of a semiconductor switch using a MOSFET, reverse current can flow through the diode.

[0065] To prevent this, the precharge relay 13 can be configured as a back-to-back structure, wherein the diodes included in the first semiconductor switch 131 and the second semiconductor switch 132 are arranged in opposite directions. Due to the opposing diodes, when the semiconductor switches are in the off state, current cannot flow through the diodes in any direction.

[0066] According to another embodiment of the present invention, the first main relay 11 and the second main relay 12 may be structures using relays of different types from each other.

[0067] For example, when the first main relay 11 is a mechanical relay, the second main relay 12 can be made of a semiconductor relay; conversely, when the first main relay 11 is a semiconductor relay, the second main relay 12 can be made of a mechanical relay.

[0068] At this time, as mentioned above, the relays that are mechanical relays in the first main relay 11 and the second main relay 12 can be electronic fuse relays.

[0069] Figure 5 This is a schematic structural diagram of the battery system included in the battery disconnection unit of another preferred embodiment of the present invention.

[0070] According to another embodiment of the present invention, the battery disconnection unit 20 may include a first main relay 21, a second main relay 22, a precharge relay 23, and a control unit 24.

[0071] When a mechanical relay with an electronic fuse, including sensor 25, is used as the first main relay 21, the precharge relay 23 can be a semiconductor relay.

[0072] When the precharge relay 23 is a semiconductor relay, the initial inrush current can be limited by not using the precharge resistor and adjusting the switching cycle of the semiconductor relay during the initial charging period.

[0073] Therefore, the battery disconnection unit 20 according to another embodiment of the present invention may not include a pre-charge resistor.

[0074] When the pre-charge resistor is not included, the pre-charge relay 23, which is a semiconductor relay, can also be used as a main relay.

[0075] That is, when the first main relay 21 fails and is disconnected, the precharge relay 23, which is a semiconductor relay, is used to connect the battery 5 and the inverter 2, thereby replacing the function of the main relay.

[0076] In this case, the types of the pre-charge relay 23 connected to the positive terminal and the second main relay 22 connected to the negative terminal in the main relay can be different.

[0077] Figure 6 This is a schematic structural diagram of the second main relay, which is a preferred embodiment of the present invention.

[0078] According to another embodiment of the present invention, the second main relay 22 can be a structure in which a mechanical relay 221 and a semiconductor relay 222 are connected in parallel.

[0079] The second main relay 22 can selectively or simultaneously connect the mechanical relay 221 and the semiconductor relay 222 according to the control of the control unit 24.

[0080] When the first main relay 21 is a mechanical relay or an electronic fuse relay and operates as a main relay, the control unit 24 can connect the semiconductor relay 222 of the second main relay 22, so that the two relays are of different types.

[0081] When the first main relay 21 fails and the precharge relay 23, which is a semiconductor relay, operates as the main relay, the control unit 24 can activate a relay of a different type than the precharge relay 23 by connecting the mechanical relay 221 of the second main relay 22.

[0082] As described above, by changing the type of the second main relay 22 as needed, the overall stability of the battery disconnection unit 20 can be further improved.

[0083] As described above, the battery disconnection unit according to this utility model, by using electronic fuse relays and semiconductor relays, allows for different types of relays included in the battery disconnection unit, thereby improving the reliability of the semiconductor disconnection unit.

[0084] The scope of protection of this utility model is not limited to the embodiments described and illustrated above. Furthermore, it should be specifically stated that obvious modifications or substitutions within the technical field to which this utility model pertains do not limit the scope of protection of this utility model.

Claims

1. A battery disconnection unit, characterized in that, include: The first main relay is connected between the positive terminal of the battery and the positive terminal of the inverter. The second main relay is connected between the negative terminal of the battery and the negative terminal of the inverter. A pre-charge relay, connected in parallel with the first main relay, performs initial charging of the DC link capacitor connected in parallel with the inverter, and The control unit includes one or more processors and a memory, and the control unit controls the connection or disconnection of the first main relay, the second main relay and the precharge relay; The first main relay and the precharge relay are composed of relays of different types from each other.

2. The battery disconnection unit according to claim 1, characterized in that, The first main relay is an electronic fuse relay, which includes a mechanical relay and a sensor for sensing the voltage or current between the battery and the inverter. The control unit connects or disconnects the mechanical relay based on the voltage or current measured by the sensor.

3. The battery disconnection unit according to claim 1, characterized in that, The second main relay is composed of a relay of a different type than the first main relay.

4. The battery disconnection unit according to claim 3, characterized in that, When the first main relay is a semiconductor relay, the second main relay is an electronic fuse relay. The electronic fuse relay includes a mechanical relay and a sensor for sensing the voltage or current between the battery and the inverter. The control unit connects or disconnects the mechanical relay based on the voltage or current measured by the sensor.

5. The battery disconnection unit according to claim 1, characterized in that, The precharge relay is a semiconductor relay.

6. The battery disconnection unit according to claim 5, characterized in that, When the first main relay fails, the precharge relay acts as the main relay connecting the positive terminal of the battery and the positive terminal of the inverter.

7. The battery disconnection unit according to claim 5, characterized in that, It also includes a precharge resistor connected between the precharge relay and the positive terminal of the inverter.

8. The battery disconnection unit according to claim 1, characterized in that, The second main relay is a structure in which a mechanical relay and a semiconductor relay are connected in parallel.

9. The battery disconnection unit according to claim 5, characterized in that, The semiconductor relay is a back-to-back structure consisting of a pair of semiconductor switches connected in opposite directions of energization.

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