Impact of input and output voltage perturbation on the behavior of automotive multi-phase converters with coupled inductors

The impact of input and output voltage perturbations on the behavior of automotive multi-phase converters with coupled inductors has been analyzed. Results have shown that voltage disturbances on the automotive energy net can lead to significant equalizing currents in the converter and perhaps to core saturation or even system failure, if adequate balancing control is not adapted. Analyses have been performed to predict the equalizing currents in the coupled inductors dependent on the input and output perturbations. A full size automotive prototype converter with four interleaved phases and coupled inductors has been built and tested. Measurements with the four-phase prototype converter are in close correlation with theoretical predictions.