The Earthquake Safety Assessment of 1000 kVA Cast Resin Transformer by Finite Element Analysis with Mesh Convergence and Seismic Test on the Large Shaking Table Under Korean and IEEE Seismic Standards

A 1000 kVA cast resin transformer (CRT) is an electrical device that reduces the amount of voltage flow for end-consumers to use safely. This paper describes seismic response analysis by numerical finite element analysis (FEA) using ANSYS and the seismic test for the Korean peninsula and IEEE-693 seismic standards. The CRT is mounted on the shaking table for seismic test carried out at KIMM (Korea Institute of Machinery and Material) to see the stress level and safety. Several FEA analysis steps are performed to match the fundamental natural frequency from resonance search test. In addition, convergence test of element’s mesh size shows that the natural frequency decreases when mesh size becomes smaller. Also, optimization is performed to find the Young’s modulus considering special stiffness characteristics of laminated core in CRT. Both the natural frequency and stress results from the numerical computation and seismic test are close and show adequate electrical and structural safety margin judged by the American Society of Civil Engineering design code for the maximum earthquake rate.