Operational Study and Protection of a Series Resonant Converter with DC Current Input Applied in DC Current Distribution Systems

Constant dc current distribution has been preferred for long distance high reliability systems such as subsea ocean observation networks. The characteristics of dc current distribution and series resonant converters (SRCs) with constant input current bring new challenges and difficulties related to protection as well as operation of individual SRC modules and the entire system. This work proposes new protection techniques for SRCs operating with a constant input current and control strategies for SRC modules. Simulation and hardware results are provided for a system consisting of two 100 km submarine cables carrying a DC current of 1 A, and two series connected 250 kHz, 1 kW SRCs that regulates the output current to 0.33 A.