Parameter Analysis and Shaking Table Test Based on Mechanics Analysis in Seismic Isolation System of Transformer with Bushings

Abstract

Earthquake damage many times in history indicate thatthe destroy type of large power transformer is diverse in earthquake andvulnerability is very high. Isolationtechnology can effectively reduce seismic response of the transformer and bushings,but transformer isolation layer design and parameter selection have a largerimpact on the isolation effect. Firstly, one transformer model installing 220,500kV real bushings for testing and analysis is designed which its structural dimension is closer totrue transformer. Multi-particle analysis model of the transformer withbushings isolation system (TBIS)and the equations of motion are established, and calculationprocedures are compiled using MATLABprogram. Secondly, impacts analysis on equivalent horizontal stiffness and dampingratio of the isolation layer are carried out subjectedto earthquake. Reasonable ranges ofstiffness and damping parameters have been determined. Earthquake simulatortesting of the transformer with real bushings is implement which transformertank filled with water in the test. Acceleration, displacement and stressresponse of transformer and bushings with or without isolation bearings wereobtained. Analysis and experiments show that the rational designing isolationlayer parameters can effectively reduce the seismic response of transformers andbushings. In conclusion, mentioned above research have reference role toseismic isolation design and application for power transformer and bushings forthe future.