Arc Suppression Method Based on Modular Multilevel Converter in Distribution Network

To solve the problem of single line-to-ground fault in distribution network (DN), this paper proposes an active voltage arc suppression method based on modular multilevel converter (MMC). However, how to maintain branch energy balance is a difficult problem in the application of MMC. Aiming at this problem, a branch energy balance control method based on circulating current and common mode voltage injection is proposed. Under the proposed method, there is no coupling between adjustment quantities in the system control, which reduces the design difficulty of controllers. On the output side of the system, the MMC can output high-quality alternating current, and the effect of arc suppression is obvious.