This paper proposes a fault-tolerant method for the half-bridge based modular multilevel converter (MMC). Fault-tolerance is able to enhance reliability which is one of the crucial issue for the MMC with a large number of switching devices. In this paper, the faulty condition of the MMC is analyzed and the detail of the proposed fault-tolerant method is described. When a switching device fault is occurred in a SM, the proposed method balances the three-phase line-to-line voltages and currents and does not require redundant submodules (SMs), which reduce the cost and volume of the MMC. To verify the fault-tolerant ability of the proposed method, various simulation results are included.
This research was supported by the KEPCO under the project entitled by \u201cDemonstration Study for Low Voltage Direct Current Distribution Network in an Island\u201d (D3080)
