Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions

HELECTRICITY H02Electric power H02HEMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS

H02H7/00Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions

H02H7/001for supra-conducting apparatus H02H7/003for electrostatic apparatus H02H7/005for remote controlled apparatus; for lines connecting such apparatus H02H7/006for non-insulated low-voltage distribution systems H02H7/008for protective arrangements according to this subclass H02H7/04for transformers H02H7/042for current transformers H02H7/045Differential protection of transformers H02H7/0455taking into account saturation of current transformers H02H7/05for capacitive voltage transformers H02H7/055for tapped transformers or tap-changing means thereof H02H7/06for dynamo-electric generators for synchronous capacitors H02H7/062for parallel connected generators H02H7/065against excitation faults H02H7/067on occurrence of a load dump H02H7/08for dynamo-electric motors H02H7/0805for synchronous motors H02H7/0811for dc motors H02H7/0816concerning the starting sequence H02H7/0822Integrated protection, motor control centres H02H7/0827responsive to underload or no-load H02H7/0833for electric motors with control arrangements H02H7/0838with H-bridge circuit H02H7/0844Fail safe control H02H7/085against excessive load H02H7/0851for motors actuating a movable member between two end positions H02H7/0852directly responsive to abnormal temperature by using a temperature sensor H02H7/0853specially adapted for motors rotating in both directions H02H7/0854responsive to rate of change of current, couple or speed H02H7/0855avoiding response to transient overloads H02H7/0856characterised by the protection measure taken H02H7/0857by lowering the mechanical load of the motor H02H7/0858by reversing, cycling or reducing the power supply to the motor H02H7/0859avoiding restarting after fault condition has disappeared H02H7/09against over-voltage against reduction of voltage against phase interruption H02H7/093against increase beyond, or decrease below, a predetermined level of rotational speed H02H7/097against wrong direction of rotation H02H7/10for converters for rectifiers H02H7/103for rotating converters H02H7/106for dynamic converters H02H7/12for static converters or rectifiers H02H7/1203Circuits independent of the type of conversion H02H7/1206specially adapted to conversion cells composed of a plurality of parallel or serial connected elements H02H7/1209for converters using only discharge tubes H02H7/1213for DC-DC converters H02H7/1216for AC-AC converters H02H7/122for inverters H02H7/1222responsive to abnormalities in the input circuit H02H7/1225responsive to internal faults H02H7/1227responsive to abnormalities in the output circuit H02H7/125for rectifiers H02H7/1252responsive to overvoltage in input or output H02H7/1255responsive to internal faults H02H7/1257responsive to short circuit or wrong polarity in output circuit H02H7/127having auxiliary control electrode to which blocking control voltages or currents are applied in case of emergency H02H7/16for capacitors H02H7/18for batteries for accumulators H02H7/20for electronic equipment H02H7/205for controlled semi-conductors which are not included in a specific circuit arrangement H02H7/22for distribution gear H02H7/222for switches H02H7/224Anti-pump circuits H02H7/226for wires or cables H02H7/228for covered wires or cables H02H7/24for spark-gap arresters H02H7/26Sectionalised protection of cable or line systems H02H7/261involving signal transmission between at least two stations H02H7/262involving transmissions of switching or blocking orders H02H7/263involving transmissions of measured values H02H7/265making use of travelling wave theory H02H7/266involving switching on a spare supply H02H7/267for parallel lines and wires H02H7/268for dc systems H02H7/28for meshed systems H02H7/30staggered disconnection