INTERNAL DAMAGE PROTECTION DEVICE FOR POWER TRANSFORMERS Russian patent published in 2021 - IPC H02H7/45 

FIELD: electrical engineering.

SUBSTANCE: invention relates to electrical engineering. The device consists of a power transformer with an on-load tap changer (OLTC), current sensors, voltage sensors, units for determining the power of the winding bushings, a winding temperature sensor, a unit for determining power losses in the power transformer, a unit for determining a power balance, high-voltage switches and a unit for diagnosing the technical condition of the power transformer. The power transformer is connected with the on-load tap-changer by communication channels, current, voltage, winding temperature sensors and high-voltage switches. The current and voltage sensors are connected to the unit for determining the power of the winding inputs by communication channels. The current, voltage and temperature sensors of the windings are connected by communication channels with the unit for determining the power losses in the transformer. The units for determining the power and the unit for determining the power losses in the power transformer with the OLTC are connected by communication channels to the unit for determining the power balance. The high-voltage switches are connected to the power balance determination unit. The power balance determination unit is connected by communication channels to the power transformer health diagnostic unit.

EFFECT: invention provides ability to determine internal faults, thereby reducing the likelihood of faulty actuation (non-actuation) of relay protection based on the analysis of power imbalance under real conditions.

1 cl, 2 dwg