Asymmetrical two-phase induction motor speed controlled by multilevel inverter employing cascaded transformers

Abstract

This research presented multilevel inverter using cascade transformers to supply the output voltage levels which are used to control speed of asymmetrical two-phase induction motor. Two sets of full bridge inverters and transformer with difference of number of turn ratio are combined to generate the voltage levels to supply each winding of asymmetrical two-phase induction motor. Triangular multicarrier sine pulse width modulation signal was generated by Arduino Due AT91SAM3X8E microcontroller and IC number IR2130 was used for power circuit. Multilevel inverter was presented to use a low level of input voltage as multilevel of output voltage is high that voltage stress on switches are reduced. The experiment shows the result of speed controlled by volt per hertz constant so as to be sure steady torque and PI method technique was used to closed-loop control.