Comparison of different voltage control strategies for current regulated PWM inverters supplying an induction motor

Output voltage of current regulated pulse width modulated (CRPWM) inverter is dependent on the state of its switches and the status of a switch is determined by the error signal between actual current and reference current. The two level voltage waveform of the CRPWM inverter is a nonlinear function of error signal. In this paper a system with a CRPWM inverter and control blocks is introduced, which by means of proper control strategies makes it possible to control the output voltage of CRPWM inverter. Three methods for voltage control of CRPWM inverters are discussed and compared to each other. The main behavior focused on in this paper is start-up dynamics of the inverter. The simulation results show that the voltage and current at load terminals is nearly sinusoidal and the harmonic content is very low