Research On Current Harmonic Suppression And Fault Tolerant Control Of Six-Phase Permanent Magnet Synchronous Motor

With the advancement of technology,the technological development of permanent magnet synchronous motors has also increased rapidly.Six-phase permanent magnet synchronous motors are not only the unique characteristics of series permanent magnet synchronous motors,but also accompanied by an increase in the number of phases.Many advantages,such as higher reliability,low voltage and high power operation,and the ability to reconstruct the torque ripple and bias fault tolerance characteristics.Here,six-phase permanent magnet synchronous motor is taken as the research object,and the phase stator current harmonics generated by it are suppressed,and the fault-tolerant control is studied when the inverter motor has a single-phase open circuit fault.This article first models the six-phase permanent magnet synchronous motor,and analyzes it based on the structural characteristics of the two Y-connected spindles.The motor model of dq coordinate transformation is analyzed and studied separately.First,when the vector space decompression(VSD)coordinate transformation method is used,the harmonic segments of the motor are projected in different subspaces respectively,so the six-phase voltage source inverter uses the four-vector SVPWM algorithm to The magnetic synchronous motor performs vector control.Thirdly,in order to eliminate the influence of harmonic current components on motor operation in different subspaces,corresponding current controllers are designed and controlled in different harmonic subspaces.In view of its characteristics,this paper proposes a method using a new type of controller combination and an internal model PI controller plus multiple proportional asynchronous controller joint control.The five-time,seven-time,11-time and 13-time six-phase permanent magnet synchronous motors The sub-harmonics are suppressed to ensure that when the motor outputs the same torque,to obtain better control performance and make the motor run more stable.Finally,according to the higher fault-tolerant characteristics of the six-phase permanent magnet synchronous motor,the traditional current hysteresis control strategy is analyzed.In view of the limitations and shortcomings of the hysteresis fault-tolerant control,this paper proposes a vector space decompression(VSD)Under the single-phase open circuit fault under coordinate transformation,combined withthe internal model PI controller plus proportional synchronous controller joint control feedforward compensation new motor model,the model can effectively retain the motor voltage,flux,torque relationship equations.It can still maintain normal operation under fault conditions.