Redundancy Of Dual Three-phase Permanent Magnet Synchronous Motor Based On Parameter Adaptive

The dual three-phase permanent magnet synchronous motor group(DTP-PMSM)has the advantages of high efficiency,strong redundancy and small torque ripple.Compared with the traditional three-phase motor,it is widely used in electromagnetic equipment,power electronics,new energy vehicles and other fields due to its rich voltage vector and low-voltage high-power output.However,when the motor was broken or disturbed,it would cause threephase current and torque ripple,which would reduce the motor control performance.In order to reduce the torque ripple range and speed error and improve the convergence speed,this paper studied the parameter adaptive sliding mode variable structure control strategy and redundant control strategy of DTP-PMSM through simulation analysis.Firstly,established a mathematical model of DTP-PMSM in both natural and rotational coordinate systems.By analyzing the strong coupling and nonlinear characteristics of the mathematical model,used Simulink for validation analysis.Secondly,the Sliding mode control strategy of DTP-PMSM was studied,and the influence of harmonic current on torque was analyzed.A current suppression strategy using quasi proportional resonant regulator to improve PI regulation was proposed,and the sliding mode current observer was improved to optimize and improved the exponential reaching law.Then,based on the equivalent circuit model of the permanent magnet synchronous motor in the rotating coordinate system,mathematical models of the permanent magnet synchronous motor under non fault and fault conditions are established and simulated.Through the fault diagnosis strategy of the d-q axis stator current error between pre and post sampling intervals,the parameter changed of the three-phase permanent magnet synchronous motor under two different operating conditions are analyzed.Finally,a redundant control strategy using electronic current control torque was proposed to achieve smooth operation of the motor under phase failure.By introducing a commutation advance angle,the redundant control effect was improved,avoiding negative torque in the event of a fault and increasing the average output electromagnetic torque after the fault.Through A fault diagnosis strategy for the stator current error of d-q axis at the preand post-sampling interval and proposed that the motor could still operate stably with derating for open-phase fault through the redundant control strategy of the electronic current control torque.The diagnosis time was 0.001 s,and the power could operate stably when the power was reduced to73%,so as to realize the adaptive adjustment of the motor during normal operation,Redundancy control was achieved through fault diagnosis algorithm criteria.Through Simulink simulation analysis,it was found that when subjected to disturbances,the optimized system chattering range was reduced to [-20 rpm,20rpm],the angle phase shift was 0.2rad,and the stator current returned to normal operation within 0.1s.While ensuring observation accuracy,the overshoot was reduced to 84%,the speed error was between-5～+10,and the rotor position error was between 0～0.7.Compared to before optimization,the current waveform was smoother,the harmonic content was lower,and the system convergence speed was improved,The adaptive adjustment was completed within 0.02 seconds,and the operational efficiency of DTP-PMSM was improved.When a phase failure occurs,the fault diagnosis time was 0.001 s,the stator current was [-30 A,30A],the peak three-phase current drops to 60% of the original,the negative torque was almost eliminated,the average electromagnetic torque increases by 66%,and the power drops to 83%.