Current Harmonic Suppression Technology for Dual Three-Phase Permanent Magnet Synchronous Motor

Through the Vector Space Decomposition (VSD) method, the currents of the dual three-phase PMSM can be decomposed into the alpha-beta component that produces the flux and torque, the z1-z2 component that produces the loss, and the zero sequence component. Controlling alpha-beta current is essential for torque regulation, while controlling z1-z2 current is equally important for suppressing current harmonics generated by nonlinear factors. In this paper, the causes of circulating current in two sets of three-phase windings of dual three-phase PMSM are described in physical sense, and the harmonic current suppression technology for harmonic currents caused by motor nonlinear factors is further proposed. It can be seen by simulation and experimental results that the current suppression technology can reduce the harmonic currents in z1-z2 subspace well and improve motor operating conditions.