Numerical modeling of DC busbar contacts

The paper presents two electro-thermal numerical models which can be used for the modeling and optimization of high currents busbar contacts for DC. The models are obtained by coupling of the electric model with the thermal field problem. The coupling is carried out by the source term of the differential equation which describes the thermal field. The models allow the calculation of the space distribution of the electric quantities (electric potential, the gradient of potential and the current density) and of the thermal quantities (the temperature, the temperature gradient, the Joule losses and heat flux). A heating larger than that of the busbar appears in the contact zone, caused by the contact resistance. The additional heating, caused by the contact resistance is simulated by an additional source injected on the surface of contact. The 2D model has been solved by the finite volumes method while the 3D model, by the finite elements method. Both models were experimentally validated. Using the models, one can determine the optimal geometry of dismountable contact for an imposed limit value of the temperature.