Research on Self-shrinking Critical Current of New Liquid Metal Current Limiter

Abstract

In order to develop Liquid metal current limiter (LMCL) into the field of high voltage and fast current limiting, suppress arcing, and reduce the erosion of electrodes and cavity. This paper proposes a new type of fault current limiter (FCL) topology. This topology is composed of a new high-voltage rheostat R, a fast switch CB2, and a current-limiting reactance L1. Among them, based on LMCL, the new high-voltage rheostat R is designed. This paper does a series of related experiments. The experiment measures the current of the circuit and the arc voltage of the liquid metal. The influence of short-circuit currents and CB2 opening time T1 on the current limit is studied. The experimental results show that as the short-circuit current and CB2 opening time T1 change, the pre-arc time and arcing time of the liquid metal, the half-wave time of the current, and the current limiting efficiency of FCL also change. The 4J29 alloy is used as the channel material, and the electrode erosion after hundreds of experiments is basically negligible. Based on the research in this paper, it provides a basis for the topology and optimal design of the current limiter in the future.