Electronic switch module for traction battery system of electric vehicle, and traction battery pack

Abstract

An electronic switch module for a traction battery system of an electric vehicle, and a traction battery pack. The electronic switch module comprises a bidirectional controllable power semiconductor switch unit, a logic control unit, an input / output isolation unit, a voltage sampler 1, a voltage sampler 2, a gate driver, a current monitor and a temperature monitor. The bidirectional controllable power semiconductor switch unit comprises two groups of semiconductor thyristors, wherein one end of each of the two groups of semiconductor thyristors is connected to a first port, and the other end of each of the two groups of semiconductor thyristors is connected to a second port and a third port; the logic control unit is in communication connection with the input / output isolation unit; and an input end of the voltage sampler 1 is connected to the first port, an input end of the voltage sampler 2 is connected to the third port, and an output end of the gate driver is connected to control ends of four semiconductor thyristors. The electronic switch module integrates driving, diagnosis and high-voltage sampling, thereby increasing the fault cutting speed, and reducing the complexity of designing a BMS mainboard.

Description

An electronic switch module and power battery pack for an electric vehicle power battery system Technical Field

[0001] The utility model relates to an electronic switch module and a power battery pack for an electric vehicle power battery system, and in particular to an electronic switch module and a power battery pack capable of replacing relays in a traditional electric vehicle power battery system. Background Art

[0002] Traditional electric vehicle power battery systems use relays for on / off control in applications such as the main positive, main negative, pre-charge, and heating circuits. A power battery pack typically contains three relays: the main positive relay, the pre-charge relay, and the main negative relay.

[0003] Figure 1 shows the high-voltage circuitry within a power battery pack. It includes the main positive relay (Relay1), the pre-charge relay (Relay2), and the main negative relay (Relay3). Driver Signal 1 (Driver1) and Driver Signal 2 (Driver2) control the switching of these three relays. V1, V2, and V3 are the voltage signals that need to be sampled. The power battery pack has a single output interface. Power can only be delivered to the vehicle when the main negative relay (Relay3) and either the main positive relay (Relay1) or the pre-charge relay (Relay2) are all closed. In the event of an emergency relay failure, all relays must be disconnected to ensure the power battery pack stops outputting power, thus completely shutting off the electric vehicle. However, the relay disconnection time for a fault is in the millisecond range. Reducing this disconnection time would further improve the safety of electric vehicles. At the same time, in order to ensure the effective and reliable operation of the relay, it is necessary to design a drive circuit and a diagnostic circuit for the relay. The traditional approach is to wire the relay drive pins and the input and output pins before and after, and connect them to the battery management system main board (BMS main board) through a wiring harness. As can be seen from Figure 1, at least 9 wiring harnesses are required to achieve effective connection between the three relays and the BMS main board. The drive circuit and diagnostic circuit increase the design size and complexity of the BMS main board, which is not conducive to the integration of subsequent domain controllers in the trend of rapid development and iteration of the vehicle's electronic architecture.

[0004] Utility Model Content

[0005] Purpose of the invention: In view of the problems that the fault cut-off time of relays in existing electric vehicles is at the ms level, and that a large number of wiring harnesses are required to design drive circuits and diagnostic circuits for relays, the utility model provides an electronic switch module and a power battery pack for an automotive power battery system. The electronic switch module integrates drive, diagnosis, and high-voltage sampling, and the fault cut-off time is at the us level. In addition, the electronic switch module interacts with the controller only through data communication, which can reduce the design complexity of the BMS motherboard, optimize the spatial structure design of the power battery pack, and facilitate the integration of subsequent domain controllers.

[0006] Technical solution: To achieve the above purpose, the technical solution adopted by this utility model is:

[0007] An electronic switch module for an electric vehicle power battery system, comprising a bidirectionally controllable power semiconductor switch unit, a logic control unit MCU, an isolated input and output unit, a voltage sampler 1, a voltage sampler 2, a gate driver, a current monitor, and a temperature monitor;

[0008] The bidirectionally controllable power semiconductor switch unit includes two groups of semiconductor thyristors, each group of semiconductor thyristors includes two thyristors connected in reverse series, one end of the two groups of semiconductor thyristors is connected to the IO1 port, and the other ends of the two groups of semiconductor thyristors are connected to the IO2 port and the IO3 port respectively;

[0009] The logic control unit MCU is communicatively connected with the isolation input and output unit;

[0010] The input end of the voltage sampler 1 is connected to the IO1 port, and the output end is connected to the isolated input and output unit; the voltage sampler 1 performs high voltage sampling on the IO1 port and sends the sampling result to the logic control unit MCU through the isolated input and output unit;

[0011] The input end of the voltage sampler 2 is connected to the IO3 port, and the output end is connected to the isolated input and output unit; the voltage sampler 2 performs high voltage sampling on the IO3 port and sends the sampling result to the logic control unit MCU through the isolated input and output unit;

[0012] The input end of the gate driver is connected to the isolation input and output unit, and the output end is connected to the control end of the four semiconductor thyristors in the bidirectionally controllable power semiconductor switch unit; the gate driver receives the control signal of the four semiconductor thyristors sent by the logic control unit MCU through the isolation input and output unit, and drives the four semiconductor thyristors;

[0013] The input end of the current monitor is connected to the control end of the four semiconductor thyristors in the bidirectionally controllable power semiconductor switch unit, and the output end is connected to the isolation input and output unit; the current monitor monitors the loop current of the semiconductor thyristor and sends the monitoring result to the logic control unit MCU through the isolation input and output unit;

[0014] The input end of the temperature monitor is connected to the control end of the four semiconductor thyristors in the bidirectionally controllable power semiconductor switch unit, and the output end is connected to the isolation input and output unit; the temperature monitor monitors the temperature of the semiconductor thyristors and sends the monitoring results to the logic control unit MCU through the isolation input and output unit.

[0015] The electronic switch module provided in this case can replace the relays in existing electric vehicles. It adopts a bidirectionally controllable power semiconductor switch unit and performs switch control through the logic control unit MCU. It has functions such as self-diagnosis, high voltage collection, loop current collection, and temperature collection. At the same time, the bidirectionally controllable power semiconductor switch unit can configure and set the pre-charging circuit through the communication protocol. When the pre-charging circuit is not needed, it can be cancelled in the configuration.

[0016] Specifically, it also includes a power supply unit, the output end of the power supply unit is connected to the power interface of the logic control unit MCU and the power interface of the gate driver, connecting the logic control unit MCU and the gate driver.

[0017] Preferably, it also includes a CAN communication unit, which is communicatively connected to the isolated input and output unit; the logic control unit MCU realizes external communication through the isolated input and output unit and the CAN communication unit; this setting allows the electronic switch module to realize bus distributed connection, each electronic switch module has a specific address, and the external controller can directly access the electronic switch module through the node address to perform function configuration and data reading.

[0018] Specifically, the voltage sampler 1 and the voltage sampler 2 are connected to the connection port of the high voltage total negative electrode at the same time.

[0019] Preferably, the four semiconductor thyristors in the bidirectionally controllable power semiconductor switch unit are all MOS tubes.

[0020] Specifically, the bidirectionally controllable power semiconductor switch unit includes two groups of semiconductor thyristors, wherein the power of the two thyristors in one group of semiconductor thyristors is greater than the power of the two thyristors in the other group of semiconductor thyristors, and the group of semiconductor thyristors with high power is connected to the IO3 port, and the group of semiconductor thyristors with low power is connected to the IO1 port.

[0021] Specifically, the bidirectionally controllable power semiconductor switch unit includes four MOS transistors, which are respectively denoted as MOS transistor Q1, MOS transistor Q2, MOS transistor Q3 and MOS transistor Q4; the IO1 port is connected to the anode of MOS transistor Q1, the cathode of MOS transistor Q1 is connected to the cathode of MOS transistor Q2, and the anode of MOS transistor Q2 is connected to the IO3 port; the IO1 port is connected to the anode of MOS transistor Q3, the cathode of MOS transistor Q3 is connected to the cathode of MOS transistor Q4, and the anode of MOS transistor Q4 is connected to the IO2 port.

[0022] A power battery pack for an electric vehicle power battery system includes any of the above-mentioned electronic switch modules, a resistor R1, a load unit and a battery pack. There are two electronic switch modules, respectively denoted as electronic switch module 1 and electronic switch module 2. The positive pole of the battery pack is connected to the IO1 port of electronic switch module 1, the IO2 port of electronic switch module 1 is connected to one end of resistor R1, the other end of R1 and the IO3 port of electronic switch module 1 are connected to the high-voltage end of the load unit, the low-voltage end of the load unit is connected to the IO3 port of electronic switch module 2, and the IO1 port of electronic switch module 2 is connected to the negative pole of the battery pack.

[0023] Beneficial effects: The electronic switch module and power battery pack for the electric vehicle power battery system provided by the utility model can replace the relays in existing electric vehicles. Compared with the existing technology, it has the following advantages: 1. The electronic switch module is designed in an integrated manner, which is conducive to compatibility with subsequent domain controllers; 2. The electronic switch module is no longer a single passive component, but has intelligent potential and can be given more responsibilities, which is convenient for sharing the pressure of the main control system; 3. The electronic switch module integrates drive, diagnosis, and high-voltage sampling, and the fault cut-off time is at the us level, which improves the fault cut-off speed; 4. The electronic switch module interacts with the controller only through data communication, which can reduce the design complexity of the BMS motherboard, optimize the spatial structure design of the power battery pack, and facilitate the integration of subsequent domain controllers. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] FIG1 is a schematic diagram of the high voltage principle in a battery pack in the prior art;

[0025] FIG2 is a schematic structural diagram of the electronic switch module of this case;

[0026] FIG3 is a schematic diagram of the high voltage principle in the battery pack of this case;

[0027] FIG4 is a schematic diagram of the electronic switch modules of this embodiment using a bus distributed connection. DETAILED DESCRIPTION

[0028] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0029] As shown in Figure 2, an electronic switch module for an electric vehicle power battery system includes a bidirectionally controllable power semiconductor switch unit, a logic control unit MCU, an isolated input and output unit, a voltage sampler 1, a voltage sampler 2, a gate driver, a current monitor, a temperature monitor, a power supply unit, and a CAN communication unit.

[0030] The bidirectionally controllable power semiconductor switch unit includes two groups of semiconductor thyristors, each group of semiconductor thyristors includes two thyristors connected in reverse series, one end of the two groups of semiconductor thyristors is connected to the IO1 port, and the other ends of the two groups of semiconductor thyristors are respectively connected to the IO2 port and the IO3 port. As shown in Figure 2, the bidirectionally controllable power semiconductor switch unit in this case includes four MOS transistors, respectively denoted as MOS transistor Q1, MOS transistor Q2, MOS transistor Q3, and MOS transistor Q4. The power of MOS transistors Q1 and MOS transistor Q2 is greater than the power of MOS transistors Q3 and MOS transistor Q4. The IO1 port is connected to the anode of MOS transistor Q1, the cathode of MOS transistor Q1 is connected to the cathode of MOS transistor Q2, and the anode of MOS transistor Q2 is connected to the IO3 port. This circuit is a high-current circuit. The IO1 port is connected to the anode of MOS transistor Q3, the cathode of MOS transistor Q3 is connected to the cathode of MOS transistor Q4, and the anode of MOS transistor Q4 is connected to the IO2 port. This circuit is a low-current circuit, that is, a pre-charge circuit.

[0031] The logic control unit MCU is communicatively connected with the isolation input and output unit; the isolation input and output unit is mainly used for isolation of communication, high-voltage sampling, driving, and diagnosis to prevent the high-voltage circuit from interfering with the low-voltage circuit.

[0032] The input end of voltage sampler 1 is connected to the IO1 port, and the output end is connected to the isolated input and output unit. Voltage sampler 1 performs high-voltage sampling on the IO1 port and sends the sampling results to the logic control unit MCU through the isolated input and output unit. The input end of voltage sampler 2 is connected to the IO3 port, and the output end is connected to the isolated input and output unit. Voltage sampler 2 performs high-voltage sampling on the IO3 port and sends the sampling results to the logic control unit MCU through the isolated input and output unit. Voltage samplers 1 and 2 are both connected to the high-voltage main negative terminal connection port.

[0033] The input end of the gate driver is connected to the isolation input and output unit, and the output end is connected to the control end of the four semiconductor thyristors in the bidirectionally controllable power semiconductor switch unit; the gate driver receives the control signals of the four semiconductor thyristors sent by the logic control unit MCU through the isolation input and output unit, and drives the four semiconductor thyristors.

[0034] The input end of the current monitor is connected to the control end of the four semiconductor thyristors in the bidirectionally controllable power semiconductor switch unit, and the output end is connected to the isolation input and output unit; the current monitor monitors the loop current of the semiconductor thyristor and sends the monitoring result to the logic control unit MCU through the isolation input and output unit.

[0035] The input end of the temperature monitor is connected to the control end of the four semiconductor thyristors in the bidirectionally controllable power semiconductor switch unit, and the output end is connected to the isolation input and output unit; the temperature monitor monitors the temperature of the semiconductor thyristors and sends the monitoring results to the logic control unit MCU through the isolation input and output unit.

[0036] The output end of the power supply unit is connected to the power interface of the logic control unit MCU and the power interface of the gate driver, connecting the logic control unit MCU and the gate driver.

[0037] The CAN communication unit is communicatively connected with the isolation input and output unit; the logic control unit MCU realizes external communication through the isolation input and output unit and the CAN communication unit.

[0038] As shown in Figure 3, a power battery pack for an electric vehicle power battery system includes an electronic switch module, a resistor R1, a load unit, and a battery pack. There are two electronic switch modules, which are respectively denoted as electronic switch module 1 and electronic switch module 2. The positive pole of the battery pack is connected to the IO1 port of the electronic switch module 1, and the IO2 port of the electronic switch module 1 is connected to one end of the resistor R1. The other end of R1 and the IO3 port of the electronic switch module 1 are connected to the high-voltage end of the load unit, and the low-voltage end of the load unit is connected to the IO3 port of the electronic switch module 2. The IO1 port of the electronic switch module 2 is connected to the negative pole of the battery pack. Compared with the prior art, the electronic switch module in this example only requires 5 wires to connect to the BMS motherboard. In this example, the load unit includes a motor control unit and a charging unit.

[0039] As shown in FIG4 , a CAN node can be allocated to each electronic switch module, and a CAN bus connection can be performed through a CAN communication unit. The power supply unit can also use a bus connection method.

[0040] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the above embodiments do not limit the present invention in any form, and any technical solution obtained by equivalent replacement or equivalent transformation falls within the scope of protection of the present invention.

Claims

1. An electronic switch module for an electric vehicle power battery system, characterized in that: It includes a bidirectional controllable power semiconductor switch unit, a logic control unit MCU, an isolated input and output unit, a voltage sampler 1, a voltage sampler 2, a gate driver, a current monitor and a temperature monitor; The bidirectionally controllable power semiconductor switch unit includes two groups of semiconductor thyristors, each group of semiconductor thyristors includes two thyristors connected in reverse series, one end of the two groups of semiconductor thyristors is connected to the IO1 port, and the other ends of the two groups of semiconductor thyristors are respectively connected to the IO2 port and the IO3 port; The logic control unit MCU is communicatively connected with the isolation input and output unit; The input end of the voltage sampler 1 is connected to the IO1 port, and the output end is connected to the isolation input and output unit; The input end of the voltage sampler 2 is connected to the IO3 port, and the output end is connected to the isolation input and output unit; The input end of the gate driver is connected to the isolation input and output unit, and the output end is connected to the control ends of four semiconductor thyristors in the bidirectionally controllable power semiconductor switch unit; The input end of the current monitor is connected to the control ends of four semiconductor thyristors in the bidirectionally controllable power semiconductor switch unit, and the output end is connected to the isolation input and output unit; The input end of the temperature monitor is connected to the control ends of four semiconductor thyristors in the bidirectionally controllable power semiconductor switch unit, and the output end is connected to the isolation input and output unit.

2. The electronic switch module for an electric vehicle power battery system according to claim 1, characterized in that: It also includes a power supply unit, the output end of which is connected to the power supply interface of the logic control unit MCU and the power supply interface of the gate driver.

3. The electronic switch module for an electric vehicle power battery system according to claim 1, characterized in that: It also includes a CAN communication unit, which is communicatively connected with the isolation input and output unit.

4. The electronic switch module for an electric vehicle power battery system according to claim 1, characterized in that: The voltage sampler 1 and the voltage sampler 2 are simultaneously connected to the connection port of the high voltage total negative electrode.

5. The electronic switch module for an electric vehicle power battery system according to claim 1, characterized in that: The four semiconductor thyristors in the bidirectionally controllable power semiconductor switch unit are all MOS tubes.

6. The electronic switch module for an electric vehicle power battery system according to claim 1, characterized in that: The bidirectionally controllable power semiconductor switch unit includes two groups of semiconductor thyristors, wherein the power of two thyristors in one group of semiconductor thyristors is greater than the power of two thyristors in another group of semiconductor thyristors, and the group of semiconductor thyristors with high power is connected to the IO3 port, and the group of semiconductor thyristors with low power is connected to the IO1 port.

7. The electronic switch module for an electric vehicle power battery system according to claim 1, characterized in that: The bidirectional controllable power semiconductor switch unit includes four MOS tubes, which are respectively denoted as MOS tube Q1, MOS tube Q2, MOS tube Q3 and MOS tube Q4; the IO1 port is connected to the anode of the MOS tube Q1, the cathode of the MOS tube Q1 is connected to the cathode of the MOS tube Q2, and the anode of the MOS tube Q2 is connected to the IO3 port; the IO1 port is connected to the anode of the MOS tube Q3, the cathode of the MOS tube Q3 is connected to the cathode of the MOS tube Q4, and the anode of the MOS tube Q4 is connected to the IO2 port.

8. A power battery pack for an electric vehicle power battery system, characterized in that: It comprises any one of the electronic switch modules, resistor R1, load unit and battery pack according to claims 1 to 7, wherein the number of the electronic switch modules is two, which are respectively recorded as electronic switch module 1 and electronic switch module 2, the positive pole of the battery pack is connected to the IO1 port of the electronic switch module 1, the IO2 port of the electronic switch module 1 is connected to one end of the resistor R1, the other end of R1 and the IO3 port of the electronic switch module 1 are connected to the high voltage end of the load unit, the low voltage end of the load unit is connected to the IO3 port of the electronic switch module 2, and the IO1 port of the electronic switch module 2 is connected to the negative pole of the battery pack.

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