Circuit Level Model of Miniature Circuit Breakers

We present a black-box model of miniature circuit breakers having a realistic physical background. In compliance with basic physics, engineering know-how and magneto-hydro-dynamics arc simulations, two sets of differential-algebraic equations are derived to model air plasma chemical dynamics and its interaction with breaker's physical environment (chamber shape, splitter plates, arc traveling). A numerically efficient and accurate electrical model at the breaker terminals is proposed. Its behavior is shown by comparing simulations with short-circuit experiments. Applications are at system level, including simulation of networks with several breakers, such as multiphase switching transients, selectivity, and coordination with fuses, other breakers and surge protection devices.