Selective coordination of solid-state circuit breakers and mechanical circuit breakers in electrical distribution systems

A method of selectively coordinating a solid-state circuit breaker (SSCB) among one or more downstream mechanical circuit breakers (CBs) in an electrical distribution system, comprising:

• determining whether a short circuit current is flowing through the SSCB and one or more downstream mechanical CBs in the electrical distribution system;
• if the short circuit current is determined to be flowing, pulsing the short circuit current by repeatedly switching a solid-state switching device, through which the short circuit current is flowing in the SSCB, ON and OFF;
• limiting a root-mean-square (RMS) value of the pulsed short circuit current to a value low enough to prevent the SSCB from tripping prematurely and high enough to allow one of the downstream mechanical CBs to trip and isolate the short circuit;
• and
• switching the solid-state switching device in the SSCB OFF permanently if none of the downstream mechanical CBs trips to isolate the short circuit after a predetermined short circuit pulsing time.