30° Discontinuous PWM-Based Closed Loop Volts/Hz Control of Induction Motor Drive with Slip Regulation

Abstract

This paper proposes 30° discontinuous PWM-based closed loop volts/Hz control of induction motor drive with slip regulation. The voltage source inverter is carried out with various pulse width modulation (PWM) schemes such as continuous PWM (CPWM) and discontinuous PWM (DPWM) schemes. The inverter's performance is affected by these PWM schemes. Therefore, this paper investigates the PWM schemes for the inverter. It aims to identify a best PWM scheme based on the total harmonic distortion and torque ripple analysis for constant volts/Hz induction motor drive amongst the various PWM schemes in open loop and closed loop and also proposes a 30° DPWM-based closed-loop control. The performance investigations of various PWM schemes based on inverter-fed induction motor have been evaluated analytically and using MATLAB/Simulink environment. Experimental results have been validated. The combination of 30° DPWM with PI control and slip regulation for induction motor makes the speed control system robust and ideal for low-accuracy applications.