Electromechanical Composite Brake Control Mechanism And Method For In-Wheel Motors Drive Electric Vehicle

The brake system of the electric wheel drive vehicle is the key to ensure the safety of the vehicle.The mechanism and performance of the brake system are developing in the direction of line control,active safety and intelligence.For the safety control problem caused by the failure of the single-side drive system of the electric wheel drive vehicle,small electric wheel drive test vehicle is the research object.An electromechanical composite brake system based on motor regenerative braking system and electromechanical braking system is proposed in this paper.Through the theoretical analysis,model construction,control strategy and control method design,co-simulation and real vehicle test,the mechanism and control method of electromechanical composite brake system have been studied,and the correctness and effectiveness of the system have also been verified.The main content of this dissertation includes:First of all,combined with the characteristics of the electric wheel drive vehicle brake system,the electromechanical composite brake system including the regenerative brake system and the electromechanical braking system was designed.Based on the mathematical models of the various mechanisms of the system,dynamic models including EMB mechanisms,drive motors,complete vehicles and tires were established.And the torque is assigned.The composition of the EMB agencies and the control method of the braking torque are mainly analyzed.Using the MATLAB/Simulink software,the simulink models of each organization were built and the correctness of the various mechanisms of the brake system was verified.Secondly,in combination with the developed electric wheel drive test vehicle,a prototype of the electromechanical composite brake system was developed.The electronic parking brake system was converted into an EMB brake system.The static and dynamic performance of the developed EMB prototype was verified and the braking performance of the EMB brake system was tested.The response characteristics and braking characteristics of the motor brake system are tested.Then,test experiments of steering performance and double-shift performance were performed to verify the performance of the vehicle,and the feasibility of the developed prototype and prototype was guaranteed.Then,based on the developed electromechanical composite braking system,the electromechanical composite braking control strategy is formulated for the safety control problem caused by the failure of the single-side drive system of the electric wheel drive vehicle.Taking the vehicle's yaw rate,side-slip angle and yaw angle as the control variables,the model predictive control method and the fuzzy PID control method are used to realize the expected stability control through the distribution of four-wheel braking torque.The joint simulation of MATLAB/Simulink and Carsim is used to analyze the instability mechanism of the failure of the single-side drive system of the electric wheel drive vehicle.The designed electromechanical replication system is used for stability control.The ABS performance verification of the electromechanical composite brake system was carried out.Finally,based on the development of electric wheel drive vehicles,electromechanical composite brake system prototype and control strategy,combined with Dspace equipment,hardware in-loop controller was designed,and related experiments were completed.The series of tests include failure test of high-speed vehicle drive system and electromechanical composite brake stability control test under failure conditions.After the simulation test results were analyzed,the safety and effectiveness of the electromechanical composite brake system was finally verified.In this paper,based on the combination of theoretical analysis and experimental verification,the research on the operation mechanism and control method of the electromechanical composite brake system of electric wheel drive is realized,which lays a foundation for the implementation of the control strategy of the electric vehicle brake system.It has theoretical reference value and engineering application significance for related research.