Structural Analysis and Testing of HV Busbar Assemblies with Rigid Conductors under Short-Circuit Conditions

A general method is presented for calculating the dynamic stresses and displacements of busbar structures with rigid conductors under various short-circuit conditions, with or without reclosing on a fault. Based on a finite-element technique and modal-response superposition, this method can be used to study a complex busbar structure in its entirety, taking into account both the three-dimensional aspect of the structural components and the paths followed by the fault currents. An explicit solution for the specific modal responses enhances the efficiency of the procedure. Laboratory tests on a three-dimensional busbar model and, also, extensive field tests on the busbars of a 315-kV substation have been performed kinder various fault conditions. The experimentally determined dynamic responses are compared with the finite-element solutions. Specific conclusions are drawn regarding the structural behavior of Hydro-Québec's 315-kV substations. Practical recommendations of general interest for the fault analysis of busbar structures are included.