Anti-skid driving device for ABS (Anti-lock Brake System) of pure electric bus

Abstract

A pure electric bus ABS system driving anti-skid device comprises front wheels and rear wheels, the front wheels and the rear wheels are provided with four wheel speed sensors, and the pure electric bus ABS system driving anti-skid device is characterized in that the wheel speed sensors are connected to an ABS-ECU control unit, the upper portion of the ABS-ECU control unit is connected with a VCU through a CAN communication protocol, and the lower portion of the ABS-ECU control unit is connected with the VCU through a CAN communication protocol. The left side of the VCU is connected with other modules through a CAN communication protocol; the VCU vehicle control unit and the vehicle speed sensor are matched with each other, and the vehicle speed sensor transmits wheel speed data to the VCU vehicle control unit for analysis, so that stable running of a vehicle is guaranteed.

Description

Technical Field

[0001] The utility model belongs to the technical field of pure electric vehicles, and in particular relates to a driving anti-skid device of an ABS system of a pure electric passenger vehicle. Background Art

[0002] With the strengthening of people's environmental awareness and the development of the country's automobile industry, new energy vehicles have gradually attracted people's attention. Safe and environmentally friendly pure electric vehicles have attracted great attention from various vehicle manufacturers.

[0003] Currently, in non-commercial pure electric vehicles, the braking system is generally only matched with the ABS system due to cost control. Electric vehicles generally use direct drive, which has fast power response and large torque. It is easy to cause the drive wheels to slip on low-adhesion roads, which in turn affects the stability of the vehicle body, increases the risk of the vehicle skidding, and affects driving safety.

[0004] Based on this, in order to ensure the stability of the vehicle body and avoid the risk of vehicle tail-spinning, this design proposes a pure electric bus ABS system drive anti-skid device. Utility Model Content

[0005] The utility model aims to provide a driving anti-skid device for an ABS system of a pure electric bus.

[0006] A pure electric bus ABS system drive anti-skid device comprises: front wheels and rear wheels, the front wheels and rear wheels are equipped with wheel speed sensors, the number of the wheel speed sensors is 4, wherein the wheel speed sensors are connected to an ABS-ECU control unit, the upper part of the ABS-ECU control unit is connected to a VCU vehicle controller via a CAN communication protocol, and the left side of the VCU vehicle controller is connected to other modules via a CAN communication protocol.

[0007] Preferably, the right side of the VCU vehicle controller is connected to the MCU microcontroller via the CAN communication protocol, and the lower part of the MCU microcontroller is connected to the drive engine via the CAN communication protocol.

[0008] Preferably, the right side of the lower part of the VCU vehicle controller is connected to the BMS battery management system, the right side of the BMS battery management system is connected to the power battery through the CAN communication protocol, the right end of the power battery is connected to the drive motor through a high-voltage wiring harness, the right side of the drive motor is connected to the rear wheel differential through a drive shaft, and the rear wheel differential is connected to the rear wheels.

[0009] Preferably, the drive motor control intervention condition is that the left and right wheel speed difference of the drive wheel is greater than a set value A, and the set value A is 12kph. If the left and right wheel speed difference of the drive wheel is greater than 12kph, it is considered that the vehicle is at risk of skidding on an oncoming road.

[0010] Preferably, the drive motor control intervention condition is that the difference between the average wheel speed of the driving wheel and the average wheel speed of the driven wheel is greater than a set value B, the set value B is 4kph, and the average wheel speed calculation formula is: (left wheel speed + right wheel speed) / 2. When the difference between the average wheel speed of the driving wheel and the average wheel speed of the driven wheel is greater than 4kph, it is considered that the vehicle is in an unstable state.

[0011] Preferably, the drive motor control access condition is that when the slip rate of the wheel speed on the same side is greater than but not in the range of 2% to 26%, the vehicle is considered to have a risk of skidding, and the slip rate calculation formula of the wheel speed on the same side is: (driving wheel speed-driven wheel speed) / driving wheel speed*100%.

[0012] The beneficial effects of the above scheme are:

[0013] 1. The utility model cooperates with the VCU vehicle controller and the vehicle speed sensor. The vehicle speed sensor transmits wheel speed data to the VCU vehicle controller for analysis to ensure the smooth driving of the car. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is the control principle diagram of the electric vehicle of the utility model;

[0015] Figure 2 This is a schematic diagram of the active torque reduction of the MCU microcontroller of the utility model. DETAILED DESCRIPTION

[0016] The present invention is further explained in detail below in conjunction with the accompanying drawings of the specification, but the protection scope of the present invention is not limited thereto.

[0017] according to Figure 1 As shown, a pure electric bus ABS system drive anti-skid device includes: front wheels and rear wheels, the front wheels and rear wheels are equipped with wheel speed sensors, the number of the wheel speed sensors is 4, the wheel speed sensors can monitor the wheel speed, wherein the wheel speed sensor is connected to the ABS-ECU control unit, the upper part of the ABS-ECU control unit is connected to the VCU vehicle controller through the CAN communication protocol, the left side of the VCU vehicle controller is connected to other modules through the CAN communication protocol, the real-time data of the wheel speed sensor is transmitted to the ABS-ECU control unit through the wheel speed acquisition harness, and then transmitted to the MCU microcontroller through the ABS-ECU control unit through the VCU vehicle controller.

[0018] Specifically, the right side of the VCU vehicle controller is connected to the MCU microcontroller through the CAN communication protocol, and the lower part of the MCU microcontroller is connected to the drive engine through the CAN communication protocol. After the MCU microcontroller performs calculations and analysis, it sends instructions to the drive motor to control the motor.

[0019] Specifically, the right side of the lower part of the VCU vehicle controller is connected to the BMS battery management system, the right side of the BMS battery management system is connected to the power battery through the CAN communication protocol, the right end of the power battery is connected to the drive motor through a high-voltage wire harness, the right side of the drive motor is connected to the rear wheel differential through a transmission shaft, and the rear wheel differential is connected to the rear wheels. The battery management system can control the amount of electricity delivered to the drive motor, thereby stabilizing the car and preventing it from skidding.

[0020] Specifically, the drive motor control intervention condition is that the left and right wheel speed difference of the drive wheel is greater than a set value A, and the set value A is 12kph. If the left and right wheel speed difference of the drive wheel is greater than 12kph, it is considered that the vehicle is at risk of skidding on an oncoming road.

[0021] Specifically, the drive motor control intervention condition is that the difference between the average wheel speed of the driving wheel and the average wheel speed of the driven wheel is greater than a set value B, and the set value B is 4 kph. The average wheel speed calculation formula is: (left wheel speed + right wheel speed) / 2. When the difference between the average wheel speed of the driving wheel and the average wheel speed of the driven wheel is greater than 4 kph, it is considered that the vehicle is in an unstable state.

[0022] Specifically, the drive motor control access condition is that when the slip rate of the same-side wheel speed is greater than but not in the range of 2% to 26%, the vehicle is considered to have a risk of skidding. The slip rate calculation formula of the same-side wheel speed is: (driving wheel speed-driven wheel speed) / driving wheel speed*100%; during vehicle operation, the VCU monitors the wheel speed signal output by the ABS system at all times, calculates the current slip rate, and performs PI adjustment based on the slip rate as a target to limit or reduce the driving torque. When the vehicle speed is greater than 30kph, the slip rate target is set to 26%; when the vehicle speed is less than 10kph, the slip rate target is set to 15%; otherwise, the slip rate at the previous moment is maintained, and the driving wheel slip time control target is that the first slip time is less than 3S, and the slip time during acceleration is less than 2S;

[0023] In actual use, the utility model monitors the four-wheel speed signals output by the ABS system through the VCU vehicle controller, calculates the slip rate through the MCU single-chip computer, and analyzes whether the vehicle is in a stable state, thereby controlling the driving torque to stabilize the vehicle. The overall control logic is as follows: the VCU vehicle controller serves as the system center, detects the driver's driving intention (accelerator pedal opening, brake pedal opening, gear position, etc.), calculates the current driver's torque request, and when the VCU vehicle controller detects that the driver has a braking intention, the VCU vehicle controller controls the MCU single-chip computer to enter the power generation state to realize the energy recovery function; when the VCU detects that the driver "floors the accelerator" and the wheel speed and vehicle speed difference are greater than the specified value, the VCU controls the MCU to reduce torque to realize stable vehicle driving;

[0024] Specifically, Figure 2As shown in the figure, when the difference between the left and right wheel speeds of the driving wheels is greater than 12kph, it is considered that the vehicle is on a split road and there is a risk of drifting. The VCU controls the MCU to reduce torque to ensure smooth driving of the vehicle.

[0025] When the difference between the average wheel speed of the driving wheel and the average wheel speed of the driven wheel is greater than 4kph, the vehicle is considered to be in an unstable state, and the VCU controls the MCU to reduce torque to achieve stable driving of the vehicle;

[0026] When the slip rate of the wheel speed on the same side is greater than but not in the range of 2% to 26%, the vehicle is considered to be at risk of skidding, and the VCU controls the MCU to reduce torque to ensure smooth driving of the vehicle.

Claims

1. A pure electric bus ABS system drive anti-skid device, comprising: The front wheels and rear wheels are equipped with wheel speed sensors, and there are 4 wheel speed sensors. It is characterized in that the wheel speed sensors are connected to the ABS-ECU control unit, the upper part of the ABS-ECU control unit is connected to the VCU vehicle controller through the CAN communication protocol, and the left side of the VCU vehicle controller is connected to other modules through the CAN communication protocol.

2. A pure electric bus ABS system driving anti-skid device as claimed in claim 1, characterized in that: The right side of the VCU vehicle controller is connected to the MCU microcontroller via the CAN communication protocol, and the lower part of the MCU microcontroller is connected to the drive engine via the CAN communication protocol.

3. A pure electric bus ABS system driving anti-skid device as claimed in claim 1, characterized in that: The right side of the lower part of the VCU vehicle controller is connected to the BMS battery management system, the right side of the BMS battery management system is connected to the power battery through the CAN communication protocol, the right end of the power battery is connected to the drive motor through a high-voltage wiring harness, the right side of the drive motor is connected to the rear wheel differential through a transmission shaft, and the rear wheel differential is connected to the rear wheels.

4. A pure electric bus ABS system drive anti-skid device as claimed in claim 3, characterized in that: The drive motor control intervention condition is that the left and right wheel speed difference of the drive wheels is greater than a set value A, and the set value A is 12kph. If the left and right wheel speed difference of the drive wheels is greater than 12kph, it is considered that the vehicle is at risk of skidding on an oncoming road.

5. A pure electric bus ABS system driving anti-skid device as claimed in claim 3, characterized in that: The drive motor control intervention condition is that the difference between the average wheel speed of the driving wheel and the average wheel speed of the driven wheel is greater than a set value B, and the set value B is 4kph. The average wheel speed calculation formula is: (left wheel speed + right wheel speed) / 2. When the difference between the average wheel speed of the driving wheel and the average wheel speed of the driven wheel is greater than 4kph, it is considered that the vehicle is in an unstable state.

6. A pure electric bus ABS system driving anti-skid device as claimed in claim 3, characterized in that: The drive motor control engagement condition is that when the slip rate of the wheel speed on the same side is greater than but not in the range of 2% to 26%, the vehicle is considered to have a risk of skidding. The slip rate calculation formula of the wheel speed on the same side is: (driving wheel speed-driven wheel speed) / driving wheel speed*100%.

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