Power loss analysis of DAB converter for SST operated in oscillating power control

An oscillating power control (OPC) has been proposed for solid-state-transformers (SST) with phase separated configuration to reduce the size of smoothing capacitors between single-phase AC/DC and DC/DC converters. This control can reduce the volume of capacitors effectively; however, it will also change the instantaneous power flow and losses in the DC/DC converter. In order to quantify the volume-loss trade-off of the SST system, how this proposed control method changes DC/DC converter losses needs to be known. This paper focuses on loss analysis and comparisons of DC/DC converter components, especially the magnetic components, with conventional and the oscillating power controls based on experiments and calculations. In addition, a new calculation method is introduced in the paper to estimate the DAB losses with the oscillating power control.