CN-114884164-B - Power battery pre-charge control circuit, vehicle and power battery pre-charge control method

CN114884164BCN 114884164 BCN114884164 BCN 114884164BCN-114884164-B

Abstract

The invention relates to the field of vehicles, in particular to a power battery pre-charge control circuit, a vehicle and a power battery pre-charge control method, which are used for outputting a high-voltage pre-charge signal by controlling an electronic fan to reverse, so that a bus capacitor is pre-charged based on the high-voltage pre-charge signal, when the voltages at the two ends of the bus capacitor are close to the total voltage of the power battery system, the relay contacts are controlled to be closed, and the technical problem that the pre-charging loop is damaged and the operation of the vehicle is affected due to repeated power on and power off in the prior art is avoided.

Inventors

WU JIAN
PAN WENJUN
MA JIEGAO
ZHANG ZHIQIANG
Qin Yinhe

Assignees

东风柳州汽车有限公司

Dates

Publication Date: 20260505
Application Date: 20220507

Claims (8)

1. The power battery pre-charge control circuit is characterized by comprising a pre-charge circuit, a switch circuit and a power battery circuit, wherein the pre-charge circuit, the switch circuit and the power battery circuit are connected in sequence; the pre-charging circuit is used for receiving a high-voltage starting signal and generating a high-voltage pre-charging signal according to the high-voltage starting signal; The pre-charging circuit comprises an electronic fan control module and an electronic fan motor, wherein the electronic fan motor comprises a primary coil winding and a secondary coil high-voltage winding; The first input end of the electronic fan control module is connected with the whole vehicle controller, the first output end of the electronic fan control module is connected with the input end of the electronic fan motor, the output end of the electronic fan motor is connected with the second input end of the electronic fan control module, and the second output end of the electronic fan control module is connected with the second end of the switch circuit, wherein the electronic fan control module is configured to respond to the high-voltage starting signal to generate a PWM pulse signal and control the electronic fan motor to rotate reversely based on the PWM pulse signal so as to output the high-voltage pre-charge signal through the secondary coil high-voltage winding; the primary coil winding is connected with a first output end of the electronic fan control module, and the secondary coil high-voltage winding is connected with a second input end of the electronic fan control module; the switching circuit is used for receiving the high-voltage pre-charging signal and controlling the switching state of the switching circuit according to the high-voltage pre-charging signal; and the power battery circuit is used for outputting a high-voltage signal to finish high-voltage power-on when the switch is closed in the opening and closing state.
2. The power cell pre-charge control circuit of claim 1, wherein the pre-charge circuit further comprises a first relay contact and a first diode; the anode of the first diode is connected with the output end of the electronic fan motor, the cathode of the first diode is connected with the second end of the first relay contact, and the first end of the first relay contact is connected with the second input end of the electronic fan control module.
3. The power battery pre-charge control circuit according to claim 1, further comprising a motor control circuit, wherein an input end of the motor control circuit is connected with the second end of the switch circuit and the second output end of the electronic fan control module, respectively; The motor control circuit is used for receiving the high-voltage pre-charge signal; The motor control circuit is also used for precharging according to the high-voltage precharge signal.
4. The power cell pre-charge control circuit of claim 3, wherein the motor control circuit comprises a first capacitor, a power control module, and a second motor; The first end of the first capacitor is connected with the first interface of the second output end of the electronic fan control module and the first input end of the power control module respectively, the second end of the first capacitor is connected with the second interface of the second output end of the electronic fan control module and the second input end of the power control module respectively, the first output end of the power control module is connected with the first input end of the second motor, the second output end of the power control module is connected with the second input end of the second motor, and the third output end of the power control module is connected with the third input end of the second motor.
5. The power cell pre-charge control circuit of claim 4, wherein the power cell circuit comprises sequentially connected battery packs.
6. The power cell pre-charge control circuit of claim 5, wherein the switching circuit comprises a second relay contact and a third relay contact; The first end of the second relay contact is connected with the positive electrode of the battery pack, the second end of the second relay contact is connected with the first interface of the second output end of the electronic fan control module, the first end of the third relay contact is connected with the negative electrode of the battery pack, and the second end of the third relay contact is connected with the second interface of the second output end of the electronic fan control module.
7. A vehicle comprising the power battery pre-charge control circuit of any one of claims 1-6.
8. A power battery pre-charge control method applied to the power battery pre-charge control circuit according to any one of claims 1 to 6, characterized by comprising: When a high-voltage starting signal is received, generating a PWM pulse signal according to the high-voltage starting signal; Controlling the running state of the electronic fan motor based on the PWM pulse signal and a preset first motor working strategy; acquiring a high-voltage pre-charging signal output by the electronic fan motor, and determining bus voltage according to the high-voltage pre-charging signal; and controlling the power battery to finish high-voltage power-on pre-charging based on the bus voltage and the preset battery pack voltage.

Description

Power battery pre-charge control circuit, vehicle and power battery pre-charge control method Technical Field The invention relates to the field of vehicles, in particular to a power battery pre-charge control circuit, a vehicle and a power battery pre-charge control method. Background The traditional electric vehicle high-voltage power-on process needs to be precharged through a precharge loop, the voltage difference at two ends of a main relay is realized, the main relay is closed again, so that large-current impact damage electrical appliance circuits caused by high voltage difference are avoided, most of traditional electric vehicles adopt a precharge loop of a precharge resistor and a precharge relay to realize high-voltage precharge power-on, but the precharge resistor can generate heat in the precharge process in the mode, the precharge loop can be damaged due to the fact that the resistor cannot be timely radiated due to frequent upper and lower electric conduction, and in addition, the precharge time is unstable due to the fact that the temperature drift is generated due to the resistance heating of the precharge resistor. Disclosure of Invention The invention mainly aims to provide a power battery pre-charge control circuit, a vehicle and a power battery pre-charge control method, and aims to solve the technical problem that the pre-charge loop is damaged and the operation of the vehicle is affected due to repeated power up and power down in the prior art. The invention provides a power battery pre-charge control circuit, which comprises a pre-charge circuit, a switch circuit and a power battery circuit, wherein the pre-charge circuit, the switch circuit and the power battery circuit are sequentially connected; the pre-charging circuit is used for receiving a high-voltage starting signal and generating a high-voltage pre-charging signal according to the high-voltage starting signal; the switching circuit is used for receiving the high-voltage pre-charging signal and controlling the switching state of the switching circuit according to the high-voltage pre-charging signal; and the power battery circuit is used for outputting a high-voltage signal to finish high-voltage power-on when the switch is closed in the opening and closing state. Optionally, the pre-charging circuit comprises an electronic fan control module and an electronic fan motor; The electronic fan control module comprises a first input end, a second input end, a first output end, a second output end, a switching circuit and a control circuit, wherein the first input end of the electronic fan control module is connected with a whole vehicle controller, the first output end of the electronic fan control module is connected with the input end of an electronic fan motor, the output end of the electronic fan motor is connected with the second input end of the electronic fan control module, and the second output end of the electronic fan control module is connected with the second end of the switching circuit. Optionally, the electronic fan motor comprises a primary coil winding and a secondary coil high-voltage winding; The primary coil winding is connected with a first output end of the electronic fan controller, and the secondary coil high-voltage winding is connected with a second input end of the electronic fan controller. Optionally, the pre-charging circuit further comprises a first relay contact and a first diode; the anode of the first diode is connected with the output end of the electronic fan motor, the cathode of the first diode is connected with the second end of the first relay contact, and the first end of the first relay contact is connected with the second input end of the electronic fan control module. Optionally, the power battery pre-charge control circuit further comprises a motor control circuit, wherein the input end of the motor control circuit is respectively connected with the second end of the switch circuit and the second output end of the electronic fan control module U1; The motor control circuit is used for receiving the high-voltage pre-charge signal; The motor control circuit is also used for precharging according to the high-voltage precharge signal. Optionally, the motor control circuit comprises a first capacitor, a power control module and a second motor; The first end of the first capacitor is connected with the first interface of the second output end of the electronic fan control module and the first input end of the power control module respectively, the second end of the first capacitor is connected with the second interface of the second output end of the electronic fan control module and the second input end of the power control module respectively, the first output end of the power control module is connected with the first input end of the second motor, the second output end of the power control module is connected with the second input end of the second motor, and the third output end of the