Investigation on the Effect of Two and Three Level PWM Inverters in Terms of Acoustic Noise Emitted by Induction Machine

Three phase Voltage Source Inverters VSI provide non-sinusoidal voltages rich in high order harmonics. The feed of power induction machine 1M by a VSI increases the level of acoustic noise which becomes unacceptable especially for applications requires a moderate level such that electrical traction. It has been found that the noise level is closely related to the voltage and current harmonic of the source feeding the machine. In addition, the harmonic level depends on the control technique used to produce the control signals. Indeed, in this paper a comparative simulation between two algorithms: (Space Vector Pulse Width Modulation SVPWM and Random Pulse Width Modulation RPWM) for both two types of voltage inverter, two-level and three- level NPC are developed and demonstrated. The simulation results show the validity and the efficiency technique for reducing acoustic noise.