Design methodology for flexible buswork between substation equipment subjected to earthquakes

Properly designed flexible buswork is one item that can increase the probability that a facility will still be operational after an earthquake. During such events, significant dynamic forces may be generated at the equipment terminals due to the push and pull of flexible connections during the motion of equipment. It is therefore important that the forces transmitted be within predetermined limits. This paper presents the results of a study aimed at obtaining sound criteria to appropriately design flexible buswork to account for seismic effects. This study was conducted with non linear finite-element simulations of representative interconnected substation equipment in existing installations, using an experimentally validated conductor model. It presents the resulting design methodology which specifies how to properly establish the required slack in a given flexible buswork configuration, as well as a predetermined level of force to be expected at the equipment terminals. Index Terms--Dynamics, earthquakes, finite-element methods, interconnections, stranded conductors, substations.