Analysis of Multi-Phase Space Vector Pulse Width Modulation Based on Multiple d-q Spaces Concept

摘要

Multi-phase motors are usually designed to have the concentrated winding and non-sinusoidal airgap flux density distribution in order to maximize the torque per ampere. This means that the phase voltage of a multiphase motor has the non-sinusoidal waveform. Accordingly, the conventional analysis on a multi-phase Space Vector Pulse Width Modulation (SVPWM), which is confined to a sinusoidal phase voltage, should be extended to a non-sinusoidal phase voltage. In this paper, based on a multiple d-q spaces concept a novel analysis on a multi-phase SVPWM to synthesize an arbitrary non-sinusoidal phase voltage is proposed. Through out this paper, a five-phase inverter is used as a practical example. The basic concepts can be easily extended to an n-phase inverter.