Abstract:
The paper focus to study on noise reduction of the line voltage of two level three phase voltage source inverter (VSI) fed induction motor (IM) at the specific frequency, and developed new PWM called Random Space Vector Pulse width modulation technique (RSVPWM) for reducing noise on line voltage. The developed RSVPWM is combining RPWM and Space vector modulation (SVPWM) technique. The paper also investigates the three-phase VSI fed induction motor and its noise behavior. The proposed method is able to create a gap in the spectrum of line voltage at selective frequency in human hearing range. Therefore, unlike conventional RPWM techniques, switching periods are determined based on the position of rotary reference vector. The paper compared with other PWM such as SPWM, RPWM and SVPWM. Among all PWM method the proposed RSVPWM generate higher voltages with low total harmonic distortion. The proposed RSVPWM is receipt less line voltage noise (10.4dB at lower modulation range and 9dB at higher modulation range). The simulation and experimentation is carried out for the full range of switching frequency of 1 kHz to 20 kHz. The modulation method can be used in both open- and closed-loop IM drive such as V/F and vector control.
