Current Limiting Characteristics of the Novel Liquid Metal Current Limiter With Different Liquid Metal Level Heights

Liquid metal current limiter (LMCL) has the advantages of simple structure and automatic current limiting. It has become a new technology to limit short-circuit current in power system. In order to improve the performance of traditional insulation partition LMCL (ILMCL), a resistive partition LMCL (RLMCL) is designed. Specifically, the force on the liquid metal liquid column model is calculated, and the motion mechanism of the liquid metal self-shrink is clarified; furthermore, a mathematical model for the liquid metal self-shrink effect is established. Using the simulation software Fluent, the dynamic diagrams of liquid metal self-shrinking gas-liquid two-phase are obtained. Finally, the current limiting characteristics and the arc plasma dynamic process of the RLMCL with different liquid metal level heights are compared and analyzed by experiments. The results indicate that the liquid metal level height is a key factor affecting the liquid metal self-shrinking speed. Whether the liquid metal fills through-hole will change the way the liquid metal shrinks. Under the same current action, as the liquid metal level height increases, the starting current limiting time, liquid metal self-shrinking time, and current half-wave time of the RLMCL increase while the peak arc voltage and arcing time gradually decrease.