Simulation of pulse width modulated (PWM) chopper drives using z-transformation

In this paper, a class-C chopper circuit is modeled using z-transformation including the time variation of the pulsewidth modulated (PWM) signal. A closed-loop speed control system using a direct current (DC) motor fed by the chopper is then simulated. In the simulation, the entire system including the DC motor, chopper, speed and current controllers are all modeled in the z-domain. Simulation has also been performed with the help of Matlab and Simulink. In addition, the closed-loop system has also been analyzed according to average value modeling and the results obtained from real-time simulation in the z-domain are compared with the results obtained from the average value model