A Single-Ended Protection Starting Element For MTDC Power Networks

HVDC can be widely interpreted as one of the remarkable transmission technological developments which connects main AC electrical grid with various nonconventional DC energy sources. The efficient power conversion capacity of modular multi-level converters (MMCs) makes their application in HVDC system very attractive. However, sudden and large increase of the fault currents upon occurrence of a DC faults creates threat for the converters and hence, demand rapid isolation. This work, a Taylor series based protection strategy is developed. The efficiency of the proposed method is tested for various worst case scenarios on two different four terminal MMC-based MTDC power system modelled using EMTDC/PSCAD and RTDS including communicational channels utilizing IEC 61850. Results show the applicability of the proposed protection method for real time and practical applications.