Simulations of electric arc behavior in hybrid LV switches

In this paper the commutation mechanism based on LV mechanical circuit breaker and parallel semiconductor device is discussed. This hybrid switch comprises electromechanical relay connected in parallel with semiconductor branch controlled by microprocessor unit. The work presented herein covers both laboratory experiments as well as EMTP-ATP simulations, where modeling of electric arc behavior was based on Cassie-Mayr black-box model with accordingly estimated parameters. Such analyses are especially important in case of hybrid switching systems due to possibility of estimating system response during transient conditions (overvoltages, current distribution, power and energy dissipated at semiconductor branch, power and energy of electric arc, etc.). Presented model provides satisfactory convergence of simulation results with data obtained during experiments.