DIFFERENTIAL METHOD OF DETECTING COIL SHORT CIRCUITS IN A THREE-PHASE TRANSFORMER Russian patent published in 2020 - IPC G01R31/06 

FIELD: electrical engineering.

SUBSTANCE: invention relates to electrical engineering, in particular to relay protection, and can be used for detection of turn-to-turn short circuits in windings of three-phase transformers. Summary: one winding of three-phase transformer is used as supply winding, to which AC voltage source with known characteristics is connected. Two other windings having one rated voltage value are used as measuring windings for detection of winding short circuits in data windings. Measuring windings of the three-phase transformer are connected so that magnetic fluxes in cores of measuring windings created by current in the supply winding are directed in one direction. Starts of measuring windings are connected together. Two ends of two measuring windings are connected to two inputs of alternating voltage or current sensor, respectively. Output of the alternating current sensor is connected to the connection point of two measuring windings. As per the readings of the sensor, compared to known values of voltage of the alternating voltage source, presence or absence of turn-to-turn closures in measuring windings is determined.

EFFECT: disclosed is a differential method of detecting coil short circuits in a three-phase transformer.

1 cl, 2 dwg