Quantitative Harmonics Performance Evaluation of High-Speed Permanent Magnet Synchronous Machine under Various Synchronous SVPWM Strategies

The advantages of high-speed permanent magnet synchronous machines (HSPMSM) include higher torque, efficiency, power density, reliability and lower maintenance cost. The fundamental frequency can be >1000Hz with relatively small inductance usually due to fewer number of turns. Consequently, for the same amount of voltage ripple, higher current ripple exists, leading to a significant amount of harmonic content. Even though wide bandgap semiconductors are gaining momentum for higher switching frequency operation, there are silicon based adjustable speed drives (ASD) limiting arbitrary high switching speed. Various synchronous space vector pulse width modulation (SVPWM) strategies have been applied in high power applications, but their effects on HSPMSM are lacking in literatures. This paper presents the quantitative current harmonics performance comparison on a 380V, 14000RPM, 0.95Nm HSPMSM. Mathematical models of PMSM, half-wave symmetry (HWS), quarter-wave symmetry (QWS), and three-phase symmetry (TPS) are described. Strategies of conventional space vector (CSVS), basic bus clamping (BBCS), and boundary sampling (BSS) are evaluated in simulation studies and analysis. Experimental platform has been established and results are obtained to validate the analytical and simulation effectiveness.