Fail-resistant solid state interruption system

Abstract

A solid state circuit interruption arrangement in a distributed power network provides fast and reliable circuit interruption. A common power source provides power to a plurality of loads via respective current paths. A main circuit breaker and a plurality of solid state circuit breakers are arranged to interrupt the current paths in response to command signals sent from a central controller. Current sensors and voltage sensors are coupled to the current paths for monitoring purposes. An automatic controller responds to any of the current sensors detecting a fault condition by automatically generating a command signal, which forces the associated solid state breaker to interrupt the associated current path. Thereafter, the controller automatically generates a signal to the main circuit breaker to interrupt the power provided from the common power source in the event that the associated current path is not interrupted by the solid state breaker. Alternatively, or in addition, the main interruption device may interrupt the current path when its own internal sensing mechanism detects a magnitude of current that is beyond a predetermined level. Also, the controller automatically generates a signal to the main breaker to interrupt the power provided from the common power source in the event that any of the branch breakers fails in the 'off' or interrupted, condition. Other features include a finned housing structure which provides cooling means for the breaker system without the need for cooling fans.