Coupled Multiphysics Field Analysis of High-Current Irregular-Shaped Busbar

Conventional rectangular busbars employed in electric power systems suffer from several drawbacks, such as containing excess conductor material and exhibiting low current densities and poor heat dissipation. Therefore, the goal of this paper is to develop an irregular-shaped high-current (2000-A) busbar based on a coupled multiphysics analysis approach in which the influences of the proximity and the skin effects were considered. First, 3-D models based on the finite-element method (FEM) are established for a conventional rectangular busbar and the proposed irregular-shaped busbar, and the current densities of the two are compared. Second, a double coupling method is employed to couple the fluid-thermal field calculations with the electromagnetic power losses, which are considered to be heat sources, to determine the proportion of convective and radiative heat transferred from the surfaces of the busbar conductors. Third, based on the electromagnetic field analysis, the dynamic and thermal stabilities of the irregularshaped busbar are verified with a new method. The time at which the short-circuit current reached a maximum is determined accurately. The electromagnetic force, temperature, and thermal stress distributions of the irregular-shaped busbar under shortcircuit conditions are obtained. Finally, the accuracy of the FEM simulations is verified by experiments, which indicate that the multiphysics field-coupled analytical approach is valid.