Electric Vehicle Turning-braking Stability Analysis And Integrated Control

At the present day, energy shortage, high demand and standards quality of life make the concept of sustainable development popular in people’s minds. With the national advocate of energy saving and emission reduction, environmental protection, the development of electric vehicles showing good situation. During the study of electric vehicles, in contrast to the conventional internal combustion engine vehicles, with the involvement of the motor and battery, showing a difference in the driving and braking. To this end, the electric vehicle modeling simulation, controller design and efficient use of energy have become a hot point in the field of electric vehicle research. Meanwhile, with the improvement of road network, vehicle automation and intelligence, vehicle stability and robustness have determined the overall performance of the vehicle. That makes the study of vehicle stability and robustness, have been a difficult and hot point for research in the control technologies.In this paper, use a miniature pure electric vehicle as the prototype for the study. At first, from the view of electric vehicles structural differences, based on vehicle dynamics, considering the operating characteristics of the motor wheel, the power performance of the car, the stability of steering, establish the electric vehicle model; and doing the simulation from the dynamic performance, braking performance, handling stability, respectively, for modeling and simulation of pure electric vehicles, the simulation results and the actual vehicle indicators are more anastomosis, indicating that the model has built is able to characterize the electric car in a certain extent, the study provides a model guarantee for the electric vehicles.In the research of electric vehicle turning-braking stability and regenerative braking, through the analysis of vehicle dynamics system, ideal brake force distribution and regulatory requirements, considering the brake energy recovery in the condition of turning and braking, emergency braking, the stability and robustness of the wheel antilock controller, designed the cooperative controller and select emergency braking condition for the simulation. Simulation results show that:the coordinated controller can be well to acbieve the set function, which to achieve the emergency brake energy recovery and anti-lock control, compared with the classic PID control, the control effect is significantly improved.In μ analysis and synthesis control of the turning and braking, taking into account the impact of the vehicle turning and braking, such as external factors, changes in the system structure, and sensor noise on the system, specific analysis the factors which affecting the robustness of the model, established the nominal model and uncertainty model, gave the weighting function and performance weighting function. From the perspective of active control, built μ integrated control framework, did the model robustness analysis for the turning and braking; use the yaw rate and roll angle speed as a reference, designed controller, and took a reduced order processing for the controller with the problem of high order. Simulation results show that:the robust controller makes the gain control of the system within the ideal range, reduced order processing controller also makes the control error in the acceptable range, and the μ analysis and integrated control of turning-braking have been completed.