Monitoring Method on Loosened State and Deformational Fault of Transformer Winding Based on Vibration and Reactance Information

In order to monitor loosened state and deformational fault for transformer winding, the monitoring method based on vibration and reactance information is proposed in this paper. Theoretical models of winding deformational state with vibration and reactance information are established and calculated. Multi-information monitoring model is established, which include vibration and reactance information monitoring method. Multi-information integrated monitoring strategy is proposed. The CEEMD-energy entropy transformation method is proposed to extract vibration feature information, and reactance feature information is extracted by reactance identification method. Aiming at a 500kVA, 35kV transformer prototype, experiment of short circuit current impact is carried on, three types of deformational windings including radial extend in middle position, axial stretching loosened and coil folding in end position are developed. Monitoring experiment on loosened state winding after multi-short circuit current impacts and three types of deformational fault windings are carried on. The monitoring results are consistent with the actual deformational state of transformer windings. Loosened state and deformational fault of windings can be monitored by proposed monitoring method based on vibration and reactance information effectively, which provide basis for multi-information monitoring.