Fault-Tolerant Operation of the DC/DC Modular Multilevel Converter Under Submodule Failure
Ramin Razani, Yasser Abdel‐Rady I. Mohamed
Abstract
This article proposes a tailored fault-tolerant operation strategy for the dc/dc modular multilevel converter (MMC) in the case of submodules (SMs) faults. The proposed strategy utilizes the unique characteristics of the dc/dc MMC to make the post-fault operation possible without the need of adding redundant SMs. These characteristics separate the fault-tolerant operation of the dc/dc MMC from the renowned dc/ac MMC and give the converter flexibility to function at different operating points. This feature allows the converter to reduce the number of SMs needed in each arm at the cost of degraded performance or reduced power transmission. The proposed strategy is investigated through three different case studies that are simulated in the MATLAB\Simulink environment. The obtained results confirmed the effectiveness of the proposed fault-tolerant operation strategy in keeping the converter operational despite several SMs faults.