Research On Carrier Phase Shift Control And Position Sensorless Control Of Dual Winding Permanent Magnet Synchronous Motor

In addition to the advantages of wide speed range,large power density and high control accuracy,dual-winding PMSM(Dual-winding PMSM)also has fault tolerance and redundancy backup capabilities.It is widely used in aerospace and medical equipment where reliability is highly required.In this paper,the research on the control strategy of three-phase dual-winding PMSM is carried out in the following two aspects:First,the application of carrier phase shift control in dual-winding PMSM has been studied.Based on the two independent control units of dual-winding PMSM,the principle of carrier phase shift control and the reason for reducing the charge and discharge current of the capacitor are analyzed.The optimal carrier phase shift angle under the SVPWM control mode is analyzed and simulated in detail.On the dSPACE experimental platform,the effectiveness of the carrier phase shift control in reducing charge and discharge current of capacitor and suppressing the DC bus current fluctuation is verified.Secondly,the influence of inductance asymmetry on the sensor-less control strategy of dualwinding PMSM is studied,and an improved error angle closed-loop control method is proposed.Each set of windings of the dual-winding PMSM in this paper are continuously arranged at 180 ° along the mechanical circumference.A Maxwell finite element simulation model is established,and the motor's winding inductance characteristics are studied.The simulation results show that when a single sub-motor is working,the three-phase inductance is asymmetric due to the asymmetric three-phase magnetic circuit,Ld and Lq are no longer constant.The mathematical model of the pulsed high frequency voltage injection(PHFVI)method is theoretically derived under the condition of asymmetrical inductance,which proves that the asymmetry of three-phase inductance will affect the accuracy of position estimation.The simulation model was established,and the start-up performance under two working modes of twin-motor and single-motor was compared and analyzed,and further verified on the experimental platform based on dSPACE.The results show that the position estimator cannot solve the rotor position when the inductance is asymmetric,so the conventional high-frequency voltage injection method is not applicable.To this end,this paper studies a double closed-loop I-F control method for error angle closed-loop directly rather than using a position estimator,so it's not sensitive to d-q-axis inductance fluctuations.Through simulation and experiment,it is proved that the dual-winding PMSM has good dynamic performance under the double closed loop I-F control when a single sub-motor is working.