Publication

Abstract : This paper presents a simple space vector based variable switching frequency PWM algorithm for induction motor drives. The classical space vector approach needs the calculation of angle, sector and reference voltage in each sampling period, which increases the complexity of the PWM algorithm. To reduce the complexity, this paper presents a simple space vector approach in which by using the phase voltages the switching times are calculated in a simple form. By using the proposed approach various switching sequences such as space vector PWM (SVPWM) basic bus-clamping PWM (BBCPWM) and advance busclamping PWM (ABCPWM) algorithms are derived. Then, the rms flux ripple which is a measure of current ripple characteristics were plotted for all the sequences. Based on the rms flux ripple characteristics, the zones of superior performance are identified. Then, in each sampling time period, the suitable sequence, which gives reduced flux ripple is applied to the. To validate the proposed algorithm simulation studies have been carried on v/f controlled induction motor drive at various modulation indices and the results are presented. The results show the effectiveness of the proposed work.