Analysis of the behavior of HVDC converter based on full-bridge submodules during DC fault conditions

The modular multilevel converters are vulnerable to DC side faults, which are severe that can destruct the system if it is not designed to withstand these kinds of faults. This paper presents an analysis of the HVDC modular multilevel converter (MMC) based on full-bridge submodules during DC side fault conditions. A detailed theoretical analysis of the behavior of the full-bridge MMC during fault conditions has been done. Despite the similarity in the operation of the half-bridge and full-bridge modular multilevel converters in normal operation, the MMC based on full-bridge submodules behaves differently in case of fault occurrence, since it has the ability to interrupt the current. The analysis has been verified by presenting the simulation results of a DC transmission system.