Black-box models for liquid nitrogen arc and its parameters optimization by PSO algorithm

Sulphur Hexafluoride (SF 6 ) has been widely utilized in the Gas Insulated Switchgear (GIS) due to its great insulation ability. However, SF 6 has great greenhouse effect. Liquid nitrogen (LN 2 ) has been considered as a promising substitute for the SF 6 gas because of its good insulation, arc quenching and cost effectiveness. To accurately simulate the LN 2 switch, it is essential to establish a mathematical model for the LN 2 arc. Black-box models have been commonly used in describing the dynamic characteristics of gas arc in circuit breaker simulations. There are numerous types of black-box models for gas arc, yet there is no literature available about the application of black-box model for the LN 2 arc. This paper aims to establish the black-box model of LN 2 arc. Based on the experimental data, several kinds of black-box models including Mayr, Cassie, Schwarz, Habedank and TP KEMA models were established, and their parameters were optimized by the Particle Swarm Optimization (PSO) algorithm. The performance of these black-box models was evaluated by the conductance error. The results indicated that black-box models can be employed for LN 2 arc simulations, and the TP KEMA model exhibits the best performance with minimal conductance errors throughout the entire arcing process.