Research On Control Of Five-phase Permanent Magnet Synchronous Motor Based On FCS-MPTC

Multi-phase permanent magnet synchronous motor(PMSM)has the advantages of high power density,more control freedom and good fault-tolerant performance compared with the traditional three-phase motor control system.At present,direct torque control(DTC)is the most widely used in the control field of multi-phase PMSM.However,the DTC algorithm has the disadvantages of large torque ripple and low equivalent switching frequency.Finite control set model predictive torque control(FCS-MPTC)can directly consider the constraints of the input and output of the controlled process to handle multivariable,highly coupled systems.It can significantly improve the shortcomings of the above DTC,and it has the characteristics of fast dynamic response and flexible control.This thesis takes five-phase PMSM as the research object,and uses FCS-MPTC as the high-performance control strategy of system.The research content of this thesis includes:(1)The mathematical model of five-phase PMSM is deduced,the similarities and differences between the five-phase drive system and the traditional three-phase system are summarized,and the spatial voltage vector distribution characteristics provided by the five-phase two-level inverter are studied;(2)The working principle of FCS-MPTC is studied,and the FCS-MPTC system suitable for five-phase PMSM is designed from several aspects such as the establishment of prediction model,design of objective function and algorithm optimization.Finally,it is compared with traditional DTC algorithm to verify the design Effectiveness;(3)There are unmodeled dynamics,parameter perturbation and uncertain disturbance factors in multi-phase PMSM control system.In order to further boost the control performance of the system,on the basis of designing traditional PI controllers and sliding mode controllers(SMC),considering motor parameter changes and uncertain disturbance factors,a novel anti-disturbance fractional order sliding mode controller(FOSMC).Finally,it is compared with traditional PI controller and sliding mode controller to verify the validity of the design;(4)In multi-phase PMSM speed control system,photoelectric conversion device is usually needed to obtain motor speed information,but high-performance,high-resolution speed acquisition equipment is not only expensive,but also vulnerable to high temperature,humidity and other adverse environment.In order to improve the value of engineering application,a five-phase PMSM speed sensor-less system is designed,and a new type of fractional order sliding mode-model reference adaptive system(FOSM-MRAS)is designed by combining model reference adaptive system(MRAS)theory and fractional-order sliding mode theory.Finally,a comparative analysis was performed with the integer-order sliding model MRAS to verify the effectiveness of the design.