Sampling Effect in SPS Modulation for Power Flow Control in Series Resonant DAB Converter

In this paper, analysis has been done to study the sampling effect due to digital implementation of the phase-shift modulation in Dual Active bridge converter (DAB). A Series Resonant DAB (SRDAB) is considered as the dual active bridge converter for transferring the power. A single-phase shift (SPS) modulation is used for power flow control in the SRDAB. The variation of the phase shift angle with respect to multisampling factor, defined as sampling to carrier frequency ratio, has been studied for the modulation technique. It is shown that the output power changes with changing multisampling factor. It is also observed that the nature of zero switching instant changes with the variation in multisampling factor. A detailed mathematical analysis has been done to identify the delay introduced due to sampling and its effect on the phase shift angle. The results are verified through the sampled SPS modulation in the MATLAB platform.