GEAR FOR PROTECTION OF POWER UNITS OF GENERATOR-TRANSFORMER AGAINST FAULTS TO GROUND ON HIGH-VOLTAGE SIDE Russian patent published in 1994 - IPC

FIELD: electrical engineering. SUBSTANCE: emergence of current in neutral of unit causes operation of current element 1. As a result signal of logic one comes to first input of AND gate. At output of AND gate 5 signal of logic one will emerge acting on second input of first actuating element 6 causing complete disconnection of unit. In consequence of operation of gear complete disconnection of unit takes place markedly earlier than current protection of zero sequence might operate. EFFECT: improved efficiency of operation of protection. 2 dwg