Redistributed pulse width modulation of MMC battery energy storage system under submodule fault condition

Battery energy storage system based on modular multilevel converter (MMC-BESS) has many advantages such as easy expansibility and high reliability. With multiple submodules (SM), the corresponding SM fault ride-through method is mandatory to reduce the construction redundancy and improve the operational reliability. This paper proposes a redistributed pulse width modulation (R-PWM) method for MMC-BESS to ride through the SM fault, which has excellent performance in different modulation indexes and can reduce the number of redundant SMs in MMC-BESS. Matlab/Simulink simulations and experimental results are presented to verify the performance of the proposed method.