PROTECTION METHOD OF SYNCHRONOUS GENERATORS AGAINST FAULT TO GROUND AT ONE POINT OF EXCITATION CIRCUIT Russian patent published in 2014 - IPC H02H7/06 G01R27/18 

FIELD: electricity.

SUBSTANCE: poles of an excitation winding are shunted by resistors, some part of which is shunted from time to time with controlled switches for the purpose of changing the state of a measuring circuit; voltages are measured on certain elements of the circuit and insulation resistance is calculated as per the formula given in the invention description. A flow chart of the method includes excitation winding (1); controlled insulation resistance (3); two shunting resistors (6) and (8); two controlled switches (5) and (9) of shunting resistors (6) and (8) respectively; ballast high-ohmic resistors (2) and (4) connected between poles of the excitation winding and switches (5) and (9); switch control unit (10); measuring unit 11; output relay unit (12); control unit (13) of good state of switches; earthing resistor (70). The technical results is achieved by decreasing the level of voltages on the shunting switches by their separation with outputs of the excitation winding by means of high-ohmic resistors, and the switches themselves for control of their good state are connected in parallel to the resistors on which voltages are measured.

EFFECT: improving operating reliability of a control system of the good state of insulation and relay protection of excitation circuits.

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