This paper investigates the feasibility of current commutation into capacitive branch in a 12kV LC DC circuit breaker (CB). Specifically, parasitic parameters in the commutation loop are identified, measured and analyzed. Two analytical models are developed: a capacitor discharge model used to extract parasitic parameters and commutation model for evaluating current transfer under arc voltage. The experimental tests on commercial Medium Voltage (MV) capacitors and busbars provide realistic input data for parameter identification. The study evaluates the commutating current, arc voltage and arcing time, which are important for developing commercial DC CB. Results confirm that passive commutation might be feasible in 12 kV DC CB, but depends on the performance of ultrafast disconnector and safety margins.
Shehu et al. (Wed,) studied this question.