Improving the Performances of Power Converters working in no-continuous duty

A power converters modulation technique particularly suitable for AC-motor working in no-continuous duty types is proposed in this paper. The algorithm is based on a variable frequency digital modulator, which allows to change the power modules switching frequency in function of the imposed operating conditions and the actual generated power losses, i.e. the power modules junction temperature, without considerably decreasing the overall drive performances. The aim is to increase the converter temperature time constant in order to make it comparable with the fed motor one