Zero-Voltage Switched Multi-Phase Converter utilizing nonlinear and coupled Inductors

A novel zero voltage switched multi-phase converter for the 42V/14V automotive electrical power system has been built and tested. The efficiency of the converter was a main target and switching losses have been reduced using non-linear inductors to achieve zero voltage switching. In comparison to resonant converters with non-linear inductors, the load current is not flowing through the non-linear inductors, reducing their size, cost and power losses. The non-linear inductors act similar to auxiliary resonant commutated poles but without additional switching devices and shape the current waveforms only during commutation. The paper outlines the converter analysis, design and measurements. Experimental results obtained are in good correlation to theoretical predictions.