An article analyzing the composition and principle of vehicle controller

(6) Fault diagnosis and treatment Continuously monitor the vehicle's electronic control system to perform fault diagnosis. The fault indicator light indicates the fault type and some fault codes. According to the fault content, timely perform corresponding safety protection treatment. For less serious faults, you can drive at a low speed to a nearby maintenance station for inspection.

(7) External charging management realizes charging connection, monitors charging process, reports charging status, and ends charging.

(8) Online diagnosis and offline testing of diagnostic equipment are responsible for the connection and diagnostic communication with external diagnostic equipment to realize UDS diagnostic services, including reading data streams, reading and clearing fault codes, and debugging control ports. The figure below is an example of a pure electric vehicle controller. It collects control signals during driving and charging to determine the driver's intention, manages and dispatches the vehicle's electronic control equipment through the CAN bus, and adopts different control strategies for different models to realize vehicle drive control, energy optimization control, brake energy recovery control and network management. The vehicle controller uses microcomputers , intelligent power drives, CAN bus and other technologies, and has the characteristics of good dynamic response, high sampling accuracy, strong anti-interference ability and good reliability.

Pure electric vehicle complete vehicle controller example

3 Vehicle Controller Design Requirements

Sensors that directly send signals to the vehicle controller include the accelerator pedal sensor, brake pedal sensor and gear switch, of which the accelerator pedal sensor and brake pedal sensor output analog signals, and the gear switch output signal is a switch signal. The vehicle controller indirectly controls the operation of the drive motor and the charging and discharging of the power battery by sending instructions to the motor controller and battery management system, and realizes the power on and off of the on-board module by controlling the main relay. According to the composition of the vehicle control network and the analysis of the input and output signals of the vehicle controller, the vehicle controller should meet the following technical requirements.

When designing hardware circuits, the driving environment of electric vehicles should be fully considered, electromagnetic compatibility should be emphasized, and anti-interference capabilities should be improved. The vehicle controller should have certain self-protection capabilities in both software and hardware to prevent extreme situations from occurring.

The vehicle controller should have multiple communication interfaces. The CAN communication interface is used to communicate with the motor controller, battery management system and vehicle information display system. The RS 232 communication interface is used to communicate with the host computer. At the same time, an RS-485 /422 communication interface is reserved , which can make devices that do not support CAN communication compatible, such as some models of vehicle touch screens.

Under different road conditions, the car will encounter different shocks and vibrations . The vehicle controller should have good shock resistance to ensure the reliability and safety of the car.