Space vector based hybrid PWM algorithm for vector controlled induction motor drives for reduced current ripple and acoustical noise

This paper presents a simplified hybrid pulse width modulation (HPWM) algorithm for vector controlled induction motor drive to reduce the steady state ripple in current and acoustical noise. The proposed HPWM algorithm is designed based on the notion of current ripple. This algorithm uses various bus-clamping PWM sequences along with the conventional space vector PWM (CSVPWM) algorithm. Modulation index and duty cycle dependent expression for rms value of the stator current ripple over a sampling interval is calculated and illustrated graphically. The, proposed HPWM algorithm selects a suitable sequence which results in lowest rms current ripple over a given sampling time interval. To validate the proposed HPWM algorithm, numerical simulation studies have been carried out and the results show the effectiveness of the proposed algorithm.