Seismic retrofitting of an HV circuit breaker using base isolation with wire ropes. Part 2: Shaking-table test validation

• Wire ropes isolators has been proposed for the seismic protection of HV circuit breakers.
• The dynamic behaviour of a 380 kV circuit breaker has been investigated by shaking table tests.
• The effectiveness of the proposed protecting system has been widely demonstratedWire Ropes reduces approximately of 75% the maximum stress level in the ceramic column

This paper addresses the experimental characterisation of a base-isolation system for the seismic qualification, of High Voltage (HV) ceramic circuit breakers, in accordance with the European standard CEI EN 62271-207. The adopted solution is based on an innovative application of wire rope isolators. The results of a preliminary investigation of an HV circuit breaker, which was base-isolated with wire ropes, were previously illustrated in a companion paper in which the effectiveness of this isolation system was analytically demonstrated. To validate these results, a shake table test campaign has been performed that includes the performance analysis of two optimal isolation system configurations. The results, which are illustrated in this paper, show both the effectiveness of this isolation system and the reliability of the proposed FE model.