Research On Predictive Control Method For Pmsm Fed By Four-Switch/Six-Switch Inverter

Permanent magnet synchronous motor has the advantages of simple structure,high work efficiency and high power density,so it has been widely used in aerospace,rail transit,and other industrial production field.However,as the key part of whole speed control system,the power switches of inverter have some hidden dangers.Once shortcircuit or open-circuit situation occurs,the speed-regulating drive system will result in large torque ripple and even burn the machine,which will definitely affect the production and even lead to safety accidents.In the meanwhile,the traditional PI control method hasn't already met the dynamic and static response capability and robustness requirements of modern industrial application scenarios for motor spe ed control systems.Hence,in order to improve the performance of speed-regulating drive system,it is becoming more and more important to study high-performance control algorithms for PMSM fed by four-switch/six-switch inverter.Firstly,the speed sensorless predictive control method for PMSM fed by four-switch inverter is proposed.The model predictive speed controller is designed to replace the PI speed regulator for PMSM vector control system fed by four-switch inverter.Considering the model-based characteristics of predictive algorithm,the discrete disturbance observer is introduced to estimate and compensate the load torque,which improves the robustness of speed-regulating drive system.Besides,a cascaded sliding mode observer is designed to estimate the position and speed of PMSM in real time.Thus,speed sensorless predictive control system for PMSM fed by four-switch inverter has been built.The correctness and feasibility of designed method are verified in MATLAB/Simulink.Then,the discrete fuzzy sliding mode FCS-MPC method for PMSM fed by fourswitch inverter is proposed.On the basis of existing speed predictive controller with disturbance compensation,the FCS-MPC current controller based on discrete fuzzy sliding mode control is designed for PMSM fed by four-switch inverter.By combining FCS-MPC control method with discrete sliding mode control method and introducing fuzzy logic control to adaptively adjust the sliding mode gain,the system robustness with respect to parameter perturbation is greatly improved.The correctness and feasibility of designed method are verified by simulation comparison experiments with traditional PI and FCS-MPC method in MATLAB/Simulink.Finally,the sliding mode predictive control method for PMSM fed by six-switch inverter is proposed.The integral sliding mode controller with NDOB is designed to replace PI speed regulator for PMSM vector control system fed by six-switch inverter.The deadbeat predictive current controller is designed to replace PI current regulator.Therefore,sliding mode predictive control system for PMSM fed by six-switch inverter has been built.Compared with traditional PI control method,the related contrast experiments in hardware-in-the-loop simulation platform for PMSM show that the proposed method can effectively improve the dynamic and static response capability and robustness of speed-regulating drive system.The thesis has 70 figures,10 tables and 62 references.