Winding Deformation Detection of Transformer Based on Sweep Frequency Impedance

Abstract

To improve the timeliness and accuracy of transformer winding deformation detection, the deformation of the transformer winding is studied by sweeping frequency impedance method. Based on the principle of scanning impedance method, an experimental test circuit is constructed to perform on-site detection on a 10 kV transformer. The results of transformer sweep impedance curve show that the simulated deformation fault has little effect on the low-frequency band of the sweep impedance curve, but the impedance amplitude shifts upward in the high-frequency band. At 50 Hz, the phase relation value of impedance changes significantly, which can be used as the basis for determining the winding deformation fault. It is proved that the sweep impedance method can be used well for the detection of transformer displacement faults with high sensitivity.