Design considerations of a three phase dual active bridge based on reactive power flow

Abstract

This paper discusses about the reactive power flow calculation in a dual-active-bridge (DAB) following the CP (conservative power) and PQ (instantaneous reactive power) theories. Based on the results from reactive power calculation, the optimal virtual turns ratio is determined so as to draw equal reactive power from the primary and secondary sides of the DAB-transformer. The equal sharing of the reactive power makes the DAB system more efficient. This paper also discusses about the computation of active and reactive power flow based on experimental data. As an example, a three winding transformer is selected for the experimentation and the better turns ratio is pointed out which can provide better efficiency.