LOW-SPEED PROTECTION METHOD FOR SHIPBOARD AC SHAFT GENERATOR Russian patent published in 1997 - IPC

FIELD: electrical engineering. SUBSTANCE: method involves overcurrent protection of excitation system components of shipboard AC shaft generator driven by main engine operating at constant speed into variable-pitch propeller when part of loads whose total power is sufficient to reduce shaft generator output power to value excluding unwanted overload of excitation system components are disconnected with preset time delay in response to signal coming from sensor to indicate decrease in main engine speed below desired value: loads to be disconnected are chosen so that those remaining on line should provided for safety in navigation and serviceability of equipment specified by standards grouped in at least two steps, each next step being disconnected when total power of preceding one is insufficient to inload shaft generator to safe value. EFFECT: improved safety in operation. 4 cl, 1 dwg