Інтелектуальний захист від однофазних замикань обмотки статора синхронного генератора, що працює в блоці з трансформатором

Abstract

The paper presents a method and protection device against single-phase ground fault of the stator winding synchronous generator working in the unit with a transformer, whose work is based on the calculation of the current at the scene of a single-phase ground fault, by using the combined principle of imposing a direct current to circle includes stator winding insulation to determine the active stator winding insulation resistance to earth, energy of discharge of pre-charged capacitor to determine the transition resistance at the site of ground fault, control of zero-sequence voltage and capacitance of stator winding insulation account to earth. The proposed protection works on the signal while lowering the insulation resistance of stator windings to earth and to disconnect the generator from the grid in case of emergency operation of the ground fault current value over setpoint. Also analyzed the properties of the proposed method and the protection devices.