Dual Three-phase Permanent Magnet Synchronous Motor Based On Sliding Mode Observer Research Sensorless Control Strategy

Asymmetrical six-phase permanent magnet synchronous motor,that is,the dual three-phase permanent magnet synchronous motor(DTP-PMSM)with a phase shift of30 degrees in the two sets of windings,with high efficiency and fault tolerance,Smaller torque ripple and other advantages,compared with traditional three-phase motors in the field of water propulsion and high-power electromagnetic equipment.In this paper,the sensorless control strategy of DTP-PMSM is researched by means of theoretical analysis,simulation analysis and experiment.First of all,based on electromagnetic principles,a mathematical model of DTP-PMSM in the six-phase natural coordinate system is established.By analyzing the strong coupling and nonlinear characteristics in its mathematical model,a mathematical model of DTP-PMSM in a synchronous rotating coordinate system is established based on the rotation coordinate transformation.Analyze and design the six-phase power inverter for DTP-PMSM,study the voltage modulation strategy,and verify and analyze it based on Matlab/Simulink software.The next,study the vector control strategy of DTP-PMSM,analyze the influence of harmonic current on torque,propose a harmonic current suppression strategy to improve the operating efficiency of DTP-PMSM,and use a quasi-proportional resonant regulator to improve PI regulation to suppress Harmonic current.For the sensorless control of DTP-PMSM,the rotor position identification strategy based on sliding mode observer is studied,and the sensorless control system based on sliding mode observer is established based on Matlab/Simulink software.Analyzing the chattering problem of the control system caused by the sign switching function of the traditional sliding mode observer,it is proposed that the saturation function is used to replace the sign switching function for sliding mode control,and the second-order generalized integrator is used to control the phase caused by the low-pass filter in the sensorless control system.Lag issues are improved.At last,based on TI’s TMS320F28375 D chip,the hardware and software of the DTP-PMSM controller were designed,and a simulation experiment test platform was built for experimental research.Under the Visual Studio development platform,the host computer debugging platform is designed and developed based on the C# language to control the DTP-PMSM and display the actual test data.Through experimental research,the DTP-PMSM sensorless control strategy,sliding mode debounce strategy and phase angle compensation strategy proposed in this paper are verified,which lays the theoretical and experimental foundation for the further research of DTP-PMSM.