A modified three dimensional space vector based PWM method for four-leg voltage source inverter fed asymmetrical two-phase induction motor

This paper presents a modified three dimensional space vector PWM method for two-phase four-leg voltage source inverter and its realization for asymmetrical two-phase induction motor. The two-phase orthogonal reference voltages are generated using the Volts/Hertz control technique in open loop and are realized using a four leg voltage source inverter. The two phase voltages are obtained by tapping the output from terminal pairs ab and cd. The three dimensional space vector modulation without null vector is used to generate the switching signals for the inverter. This technique reduces the switching losses in the inverter and the experimental and simulation results obtained validate the algorithm used.