Modular Multilevel Matrix Converter Control Method Based on Feedforward Decoupling Branch Energy Balance for Fault Arc Suppression in Distribution Networks

Equalization control and ripple suppression of sub-module capacitor voltages in modular multilevel matrix converter (M3C) is a prerequisite for stable system operation. The existing M3C control strategy is difficult to stabilize the control when the input and output are of the same frequency, and there are control variables coupled with each other in the control process, which leads to the unbalanced capacitive voltage ripple of the submodule. Aiming at the above problems, this paper proposes a M3C control method based on feed-forward decoupled branch energy equalization, and uses it in single-phase ground fault arc suppression in distribution networks. Using average theory to describe the coupling between the average power of each branch and the control variables. Decoupling is achieved using feed-forward to improve the control accuracy of the capacitor voltage. The correctness of the theoretical analysis and the effectiveness of the proposed method are verified by the hardware-in-the-loop experimental platform.