Research On Electromechanical Coupling Dynamics And Vibration Control Strategy Of Electric Drive System Of Electric Vehicle

In order to implement the decision and deployment of the State Council on developing strategic emerging industries and strengthening energy conservation and emission reduction,accelerating the cultivation and development of energy-saving vehicles and new energy vehicles is not only an urgent task to effectively alleviate the pressure on energy and the environment,and to promote the sustainable development of the automotive industry,but also to accelerate Strategic measures to transform and upgrade the automobile industry,cultivate new economic growth points and international competitive advantages.Electric vehicles are one of the main types of new energy vehicles,and the electric drive system is one of the core components of electric vehicles.The electric drive system of an electric vehicle is an electromechanical coupling nonlinear system including drive motors,motor controllers,transmission systems and other components.Mechanical and electromagnetic excitations cause electromechanical coupling vibrations in the electric drive system,which seriously affects the reliability and comfort of the system.Therefore,it is of theoretical significance and engineering value to carry out research on the electromechanical coupling vibration mechanism and vibration suppression control strategy of the electric drive system of electric vehicles.The main research contents of this paper are as follows:(1)Considering the dynamic characteristics of the permanent magnet synchronous motor and the nonlinear time-varying meshing characteristics of the gear transmission system,establish the electromechanical coupling dynamics model of the electric drive system of the electric vehicle including the dynamic model of the permanent magnet synchronous motor,the dynamic model of the gear transmission system,and the control system model.(2)Consider the time harmonic factors of permanent magnet synchronous motor due to angle sampling error,inverter dead zone,etc.,analyze the effect of permanent magnet synchronous motor time harmonic on motor electromagnetic torque and gear transmission system meshing vibration under steady-state conditions.The influence law reveals the electromechanical coupling vibration characteristics of the electric drive system under steady-state conditions.Considering the external load excitation caused by road impact,the dynamic response characteristics of electromechanical coupling of the electric drive system of electric vehicles under impact conditions are studied.(3)Based on the study of electromechanical coupling dynamics of the electric drive system of electric vehicles under steady-state conditions,for the 6n±1 order harmonic current generated by the time harmonics of permanent magnet synchronous motors,an electric vehicle electric vehicle based on harmonic current suppression is proposed The electromechanical coupling vibration control strategy of the drive system realizes the effective suppression of the 5th and 7th order harmonic current generated by the stator current by adding a compensation voltage to the original harmonic voltage,and reduces the electromagnetic torque and motor speed of the permanent magnet synchronous motor The pulsation and mechanical vibration of the gear transmission system can achieve the purpose of reducing the vibration of the electric drive system.(4)Based on the study of electromechanical coupling dynamics of the electric drive system of electric vehicles under shock conditions,an active damping control strategy based on current compensation is proposed.First,take the speed differenceΔω at both ends of the half shaft as the feedback signal of the controller,setΔω =0 as the control target value,establish an active damping controller based on PI current compensation,and verify the control strategy under impact load simulation Effectiveness.Aiming at the PI controller’s characteristics of poor robustness and insufficient adaptive ability,an active disturbance rejection controller with strong adaptability,robustness,operability,etc.is selected,and an active reduction based on active disturbance rejection current compensation is established.Vibration controller,simulation analysis of the dynamic characteristic response of the electric vehicle electric drive system of the active anti-disturbance current compensation active damping controller under shock conditions,and by calculating the control error of the two different active damping controllers,it can be realized The effective suppression of the electromechanical coupling vibration of the electric drive system of electric vehicles under shock conditions verifies the effectiveness of the active damping controller based on active disturbance rejection current compensation.