Space Vector Modulation Algorithm for Power Losses and THD Reduction in VSI Based Drives

A novel modulation technique for optimizing the performances of voltage source inverter feeding induction motor drives is presented. It is based on a variable frequency modulation technique, changing step-by-step the switching frequency of the power modules in order to achieve a reduction both of the switching losses and of the output voltage distortion. In addition, this technique is combined with the "single switch commutation" one, which allows to reduce the blank time imposition during the switches commutations. The proposed modulation strategy has been implemented by means of a digital modulator and several tests have been performed in order to verify its validity and feasibility.