Parametric Short-Circuit Force Analysis of Three-Phase Busbars: A Fully Automated Finite Element Approach

A three-phase busbar arrangement with straight rigid conductors carrying short-circuit currents is investigated. Calculations are made assuming steady-state ac current with a peak value equal to the peak value of the short-circuit current. The electromagnetic forces are calculated by solving the electromagnetic field diffusion equation numerically, using finite elements. The results are compared with results calculated according to IEC Standard 865/93. A large number of arrangements have been examined, covering a wide variety of cases, as used in ac indoor installations of medium and low voltage. For this purpose, the finite element procedure has been fully automated to a degree of minimal human intervention. A Let-It-Grow artificial neural network has been utilized for the automatic mesh generation. The forces calculated were in all cases in excellent agreement with IEC Standard 865/93.