Research And Implementation Of Control Strategy Of Feedback Brake For Electric Vehicle

The rapid development of electric vehicles has reduced oil consumption and environmental pollution,but the problem of short driving range has not been effectively solved,which limits the popularity of electric vehicles.In order to solve this problem,domestic and foreign scholars have proposed different control strategies for the braking energy recovery system.In this paper,the braking system of the electric vehicle of the predecessor type is studied.The braking energy is the sum of the braking feedback energy and the mechanical braking energy.In order to improve the feedback braking energy,the mechanical braking energy is reduced.In order to maintain a sufficient mechanical braking strength and ensure safe driving,the project increases the mechanical braking strength of the oil storage pump,and when the mechanical braking is required,the hydraulic oil is returned to the mechanical brake to complete the new braking system design.For the new feedback brake,this paper focuses on the control strategy of the feedback brake.The main research work is as follows:The paper analyzes the demand for the feedback brake control strategy.Analysis of brake system structure,and clarify the main content of the control strategy;complete the design of the control system based on the feedback brake.With the aim of braking strength,a control strategy for the feedback brake was developed.The boundary conditions of the control strategy are formulated in combination with the limiting factors such as less energy recovery at the low motor speed and overcharge and damage to the battery when the battery is high.In combination with the driver's braking intention,a control strategy is established for the electric feedback braking and the mechanical braking energy management;In order to ensure the safe and reliable operation of the system,a fault detection and processing control strategy is established to ensure the stable operation and braking safety of the new feedback brake.In the feedback brake control strategy code implementation,this paper adopts the model-based system code automatic generation method,and uses the Stateflow tool to establish the control strategy simulation model.In the RTW environment,the system file configuration and the driver module are completed,and the code is automatically generated.Set up a simple hardware experiment platform to verify the correctness of the control strategy code.Experiments have shown that the automatically generated control strategy code can stabilize the correct operation and complete the control of the feedback brake.The brake energy recovery effect verification of the feedback brake control strategy.In this paper,the MATLAB and ADVISOR co-simulation technology is used to build a pre-drive electric vehicle simulation model in MATLAB/Simulink.The simulation test was carried out under the ECE_EUDC cycle condition.The comparison with the ADVISOR's own electric vehicle energy recovery control strategy showed that the driving range of the electric vehicle using the feedback brake control strategy was increased by 4.2km,and the SOC under single cycle conditions.Consumption decreased by 6%.