METHOD FOR MATCHING RESISTANCES FOR DIAGNOSING MECHANICAL STATE OF POWER TRANSFORMER WINDINGS Russian patent published in 2023 - IPC G01R31/62 G01R31/72 

FIELD: power engineering.

SUBSTANCE: invention is related to a method for matching resistances when diagnosing the mechanical state of the windings of power transformers. A broadband transformer with a ferrite toroidal core based on nickel-zinc ferrite with a permeability of at least 100 H/m is used as a matching device, matching the windings of the studied power transformer with a resistance of measuring equipment (a measuring generator and an oscilloscope) of 50 Ohm, which enables signal transmission with level not less than +33 dBm and frequency up to 30 MHz. A matching broadband transformer has two bifilar primary windings and a secondary winding in form of a rectangular copper or aluminium busbar. One primary bifilar winding is connected to a measuring generator, the other to an oscilloscope. The secondary winding is connected to the winding of the power transformer under study.

EFFECT: increase in the dynamic range of voltage (amplitude component) of harmonic oscillations of response of the transformer winding and a decrease in losses for matching wave impedances, which are the result of improved matching of measuring equipment and switching cables with the object under study in a wide frequency range.

3 cl, 5 dwg