A Carrier-Based Unbalanced PWM Method for Four-Leg Voltage Source Inverter Fed Asymmetrical Two-Phase Induction. Motor

摘要

This paper presents a carrier-based unbalanced PWM method for two-phase four-leg voltage source inverter and its realization for asymmetrical two-phase induction motor. A modulation strategy is developed to synthesize unbalanced two-phase output voltage waveforms based on the unipolar modulation technique with open-loop V/f control. The' proposed control scheme. allows independent magnitude controllability and quadrature phase angle for unbalanced two-phase output v o l t a g e s . Thus, t h e modulation algorithm makes the four-leg voltage source inverter inequitable with unbalanced two-phase. loads.Simulation and experimental results confirm the feasibility of the control method for the inverter.