Logic-controlled solid-state switchgear for 270 volt dc.A feasibility study to design and demonstrate solid-state switchgear composed of circuit breakers and a power transfer switch is described. The switchgear operates on a nominal 270 Vdc circuit and controls power to a load up to 15 A. One circuit breaker may be interconnected to a second to form a power transfer switch. Breaker or switch on-off and transfer functions can be remotely controlled. Automatic overload trip-out is provided through an ultimate current trip and an I squared t trip for transient overcurrents lower than the ultimate current trip level. A number of reclosures with variable time delay between trip-out and reclosure are programmed and controlled by integrated analog and COSMOS logic circuits. A commutation circuit that creates minimal transient disturbances to either source or load was developed to interrupt current flow through the main SCR switching element.-
Document ID
19730058113
Acquisition Source
Legacy CDMS
Document Type
Conference Proceedings
Authors
Waddington, D.
Buchanan, E., Jr. (Martin Marietta Aerospace Denver, Colo., United States)
Sundberg, G. (NASA Lewis Research Center Cleveland, Ohio, United States)