Evaluation of a Bidirectional Single-Stage Three-Phase Converter with Wide Input Voltage Range

Abstract:
A recently proposed bidirectional isolated single-stage converter based on a dual active bridge shows soft switching behavior with minimal switch count. One characteristic of this converter is the superposition of the sixth harmonic of the mains frequency on the output current. The converter was simulated in this paper, and its concept was confirmed. By superimposing the harmonics on the phase shift angle of the dual active bridge, a method for reducing the output harmonics is presented. A 1kW dual-output prototype was built. As a DC/DC converter, an efficiency of 90% was achieved, and as an AC/DC converter, efficiencies over 80% can be expected.