Half-Bridge Submodule Test Circuit for MMC-based Voltage Sourced HVDC System

A Voltage Sourced Converter (VSC) for High Voltage Direct Current (HVDC) operates in extremely high voltage and high-power conditions. Especially in case of Modular Multilevel Converter (MMC), hundreds of submodules are connected in series to meet the high voltage requirement. IEC 62501 suggests several tests such as the operational tests for a valve consisting of several submodules and the dielectric tests, etc. This paper proposes a new test circuit for the half bridge submodule in MMC-based HVDC system. Simulations are carried out to show the validity of the proposed test circuit.