A Hybrid Modular DC-DC Converter Topology for Hybrid Interlink in HVDC

A modular dc-dc converter topology is discussed in this paper which provides an economic solution on existing modular multilevel converter (MMC) based dc-dc converters for forming a hybrid interlink in high voltage dc (HVdc) network. The number of semiconductor devices is optimized by using hybrid MMC to minimize losses and at the same time ensure dc fault clearance capability. The topology is demonstrated for three modes of operation of the dc-dc converter such as bipolar VSC to bipolar LCC, bipolar VSC to monopolar LCC and monopolar VSC to bipolar LCC dc buses with the help of simulation results in Matlab/Simulink.