Modulation and Control Method for Bidirectional Isolated AC/DC Matrix Based Converter in Hybrid AC/DC Microgrid

Isolated AC/DC matrix converter can realize AC-DC conversion with high frequency transformer to isolate the AC and DC side. Thanks to its high-power density and high efficiency, it is an attractive alternative to the conventional voltage source converter in hybrid microgird as interlinking converter, which adopts power frequency transformers when isolation is required. To realize this, bi-directional operation is essential. Aiming at regulating the active and reactive power, modulation and control strategies for an isolated AC/DC matrix converter are developed in this paper. A suitable SVPWM modulation is proposed to realize bidirectional power flow. In addition, the corresponding control scheme is also proposed, which contains two modes: the DC link voltage control mode, and active and reactive power control mode. Simulation results are given to verify the PWM method and control schemes.