Overmodulation Algorithm for Zero-Switching Modulation

This paper proposes a new overmodulation algorithm that calculates the modulation function by interpolating between the modulation waveform at the highest modulation index of the zero-switching modulation and the six-step operation of the inverter. The simple implementation has the advantages of zero-switching modulation that provides low switching losses. The strategy increases the torque/amp of the induction motor at speeds above the nominal value. This algorithm has been tested by simulation in MATLAB and implemented on a DSP-controlled drive with application in electrical or hybrid vehicles