Electrical equipment has high vulnerability under strong earthquakes due to its own material and structure characteristics. The seismic performance of electrical equipment can be effectively improved by installing isolation devices. Based on the finite element simulation, this paper establishes the finite element simulation model of the friction pendulum isolation device suitable for the main transformer electrical equipment, calculates and compares the mechanical response of the isolation device under different design parameters. The results show that the friction pendulum isolation device with conventional design can meet the load-bearing requirements of the main transformer under conventional conditions; increasing the friction coefficient can effectively improve the energy dissipation effect of the friction pendulum isolation device, but the increase of the friction coefficient will limit the design displacement of the isolation device, and the specific isolation effect needs to be further evaluated; changing the curvature radius of sliding surface has little effect on energy dissipation of friction pendulum isolation device. The research results in this paper can provide research basis for the application of friction pendulum isolation device in the field of electrical equipment.