Research On Control Strategy Of Electric Vehicle Based On Asynchronous Motor

With the increasingly serious environmental pollution,the development of electric vehicles has become a popular direction in the automotive industry.Relying on the characteristics of low cost,simple structure and reliable operation,asynchronous motors are widely used in industrial,agricultural and scientific and technological fields,and are also widely used as on-board motors for electric vehicles.In this paper,the speed loop in the vector control system of on-board asynchronous motor is taken as the main research object,which makes it more advantageous in terms of dynamic and static response and anti-disturbance performance.In view of the traditional SVPWM technology often involves too many trigonometric functions and matrix operations,this paper proposes an improved SVPWM control algorithm.When calculating the reference vector action time,it rotates part of the reference vector,uses the first sector and the sixth sector action time to replace the original sector action time,simplifies the corresponding calculation,drives the electricity through the open-loop The simulation results show that the control method has the ability of load.Due to the variable load and rotating speed of electric vehicles,the classical PID control is not effective.As a result,In this paper,PID control and fuzzy PID composite control are proposed in the speed controller of the vector control system.When the speed error is large,PID control is adopted,and when the speed error is small,fuzzy PID control is used to finetune it.The method can achieve better output and stable speed when the load changes and improve the anti-disturbance performance of the system.The initial PID parameters and quantization factors of fuzzy PID controller are mostly trial and error method.To achieve the best effect for the controller of asynchronous motor used in electric vehicle,a chaos particle swarm optimization parameter algorithm is proposed.The algorithm adopts the early decision strategy,applies the chaos algorithm to the initialization and later search of particle swarm to prevent it from falling into local optimum.At the same time,a variable scale search is proposed The algorithm increases the search range in the later period of algorithm optimization,and effectively solves the problem of parameter value.Finally,the vector control model of asynchronous motor is built on MATLAB / Simulink platform,and the simulation is carried out for the application scenario of electric vehicle.The simulation results show that PID control and fuzzy PID compound control have obvious advantages in static response and anti disturbance performance.