Seismic response of an electrical switchboard with vibration absorbers during earthquake excitation

Electrical equipment with a large size and load is often connected to a foundation using bolts. However, these bolted connections are less stable during an earthquake because they tend to loosen easily, leading to damage, deformation or breakage of the equipment inside the electrical cabinet. In this study, newly designed antivibration devices (AVDs) with dampers and pivots are proposed to ensure the stability of the electrical switchboard under seismic excitation. These AVDs consist of assembled steel panels and elastic rubber rings. The dynamic characteristics of the switchboard are evaluated through simulation and experiment with and without AVDs. Seismic excitations in different directions are investigated in this study. Results indicate that the resonant frequency of the switchboard is approximately 6 Hz, and the maximum relative displacement is reduced by at least 50 % when AVDs are used. These findings show that the proposed AVDs function effectively and can be used to control the vibration of electrical devices during earthquakes.