Shaping the HIPWM-FMTC strategy to reduce acoustic noise radiated by inverter-fed induction motors

An improvement over a recently published control strategy is presented. The goal consists in reducing the acoustic noise caused by a PWM-Controlled Induction Machine Drives. It is a technique that uses a sinusoidal modulator wave (with harmonics injection) and a modulated frequency triangular carrier signal, and after comparing them, the modulated wave is obtained. The technique generates an efficient quality voltage for low commutations per cycle and is highly suitable reducing the acoustic noise radiated for any motor. The reason for the technique being so efficient, from the acoustic point of view, is the non existence of the relevant term in the electrical spectrum as in the Random PWM techniques. The main advantage of the proposed method is that only one parameter is necessary to get control over it. Therefore, the space harmonics FMM with high winding factor are avoided modifying this parameter. Results are checked experimentally and compared to other PWM techniques.