MULTIPHASE CIRCUIT SURGE PROTECTIVE GEAR Russian patent published in 2002 - IPC

FIELD: power engineering. SUBSTANCE: series-connected highly nonlinear resistors are inserted between phases of circuit under protection. Each phase incorporates four pairs of series-connected highly nonlinear resistors disposed on edges of four-face pyramid from top to base. Points of connection of highly nonlinear resistors are interconnected in each phase and then two points of connection of adjacent phases formed in the process are interconnected by means of conductors disposed in their side planes. Conductor interconnecting two extreme phases arranged in row is passed inside phase pyramids disposed between extreme phases. Remaining voltage at rated discharge current of each top highly nonlinear resistor relates to remaining voltage at discharge current of each bottom highly nonlinear resistor 2 or 4 as . EFFECT: improved protective characteristics and operating stability of protective gear. 1 dwg