Research On The Control Strategy Of PMSM Speed Control System Based On Sliding Mode Control

Permanent magnet synchronous motors have a wide range of applications in electric vehicles,robotics,aerospace and other fields.However,most PMSMs are used in harsh environments in practice,so higher control requirements are required for them.In the face of increasingly high precision requirements and a variety of working environments,the traditional PI control can no longer meet the demands.Therefore,this paper conducts a study related to the following.For the problems of poor robustness and slow dynamic response of the PI controller,nonlinear state error feedback(NLSEF)current controller of PMSM with sliding mode speed regulation based on NDOB strategy is proposed.Firstly,in the velocity loop,a sliding mode controller based on NDOB is designed to obtain the observed current_qi~*,which suppresses the influence of uncertainties to the system.Then the NLSEF current controller based on NDOB is proposed,which enhances the rapidity and anti-disturbance capability.Finally,the effectiveness of the method is verified by simulation.For the problem that the advanced control strategies cannot follow the change of motor state to make real-time adjustment of the controller parameters,the intelligent sliding mode control strategy of PMSM speed control system is proposed.Firstly,the neural network sliding mode speed controller is designed,and the RBF neural network is used to fit the switching function of the sliding mode control and approach the unknown parameters’disturbances in the controller respectively,which enhances the robustness of the system and suppresses the chatter phenomenon.Then,the feasibility of the method is verified by simulation.In order to improve the the robustness of the PMSM control system to parameters’uptake,a neural network sliding mode control strategy based on model-free is designed.Firstly,according to the hyperlocal model of the PMSM,a model-free sliding mode controller that does not depend on the exact model of the system is designed.Then,the unknown disturbances in model-free control are approached by RBF neural network to improve the robustness of the system.Finally,the effectiveness of the control method is verified by simulation.In order to test the feasibility of the design scheme more realistically and rationally,and to obtain experimental conclusions closer to the actual application process,a semi-physical simulation experiment platform was built to verify the effectiveness of NLSEF current control of PMSM with sliding mode speed regulation based on NDOB strategy through experiments.The paper has 57 figures,7 tables,and 86 references.