AUTOMATIC FLASHOVER PROTECTION FOR LOCOMOTIVE TRACTION MOTORS

摘要

Flashover protection is provided for a locomotive propulsion system including a plurality of d-c traction motors (15, 16) each having a commutator (15A) subject to flashovers. A flashover detector (32) is provided for producing a fault signal in case a flashover occurs. In response to the fault signal, a solid-state controllable electric valve (71) connected between the excitation current source (17) and the alternator field winding (12f) is changed to non-conducting state, whereupon the magnitude of excitation current in the alternator field winding (12f) is rapidly reduced toward zero and the alternator's output current is correspondingly decreased whenever a flashover occurs.