Multi-terminal hvdc fault current analysis during line to ground fault

This paper illustrates the analysis of fault current development in a multi-terminal High Voltage Direct Current (MTDC) system based on two-level voltage source converter. The paper presents a technique to investigate individual fault current feeding components during a line-to-ground (L-G) fault. Moreover, growth of the fault currents is found individually to find the contributions from different components that behave as source at the time of fault for proposing protection schemes for the four terminal MTDC network. Impact of key parameters is taken into account by varying them in order to analyze the system critically and to validate the results. Results are verified and a comprehensive comparison is carried out through PSCAD.