Stability Analysis of Dual Active Bridge DC-DC Converter Using TCM Modulation Technique

Abstract: This paper addresses triangular current modulation technique (TCM) to reduce circulating current and losses in the dual active bridge converter (DAB). The converter is designed through small signal analysis. Stability is the challenging issue in DAB, due to the nonlinear behavior of the converter. The stability is convinced by the PI controller with a variation of switching inductance. Triangular current modulation is a type of alternate phase shift scheme in which the reduction of circulating current takes place with the help of maintaining the triangular waveform in the primary winding of the transformer. In buck mode, the system response is always stable, but in the case of the boost mode of the converter, the system will be unstable due to nonlinearity. The system can make sure to be stable with the help of the PI controller under the variation of switching inductors.

Keywords: Small signal analysis (SSA), TRM (Triangular current modulation) Dual active bridge converter (DAB)