Multiline Fault Current Limiter for DC Line Fault in Multi‐terminal DC Grids

Abstract

The current‐limiting reactor is currently the most used fault current limiting technique to ensure the fault ride‐through of the multi‐terminal dc grid. However, its configuration will significantly prolong the fault current clearance time and increase the dissipated energy of dc circuit breakers. Therefore, this paper proposes a cost‐effective multiline fault current limiter for multiport application in multi‐terminal dc grids, which can effectively limit the rising speed of fault current through the integrated current‐limiting reactors without time delay and significantly reduce their negative impacts on the performance of dc circuit breakers by bypassing the current‐limiting reactors through the solid‐state switch units during the fault current interruption process. The topology and operation process of the multiline fault current limiter are introduced at first. Then, the economic comparison of the proposed device with the existing solutions is presented. Finally, the feasibility and superiorities of the proposed device are verified by extensive simulations and scaled‐down experiments. © 2023 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.