Investigation on Effect of Fillets on the Characteristics of Relay Electrical Contacts

This article investigates the effect of various fillets on the performance characteristics of relay electrical contacts. Finite element modeling (FEM) of a relay electrical contact is designed in 3D using the COMSOL Multiphysics simulation tool. Copper material is assigned to the electrical contact pairs. Analysis is carried out for the heights of 0.5 mm and 1 mm. Also, the structure of the contact surface is fine-tuned by using different fillets of 1.5 mm, 1 mm, and 0.5 mm. The voltages of 1 V–10 V are offered, and their performance is evaluated. The key parameters to design the contacts are identified. The electrical, thermal, and mechanical analysis is carried out. The parameters such as current density, contact interface temperature, stress, and pressure are simulated using FEM. The results present the evaluation of relays with different heights through different fillets in various voltage ranges. The results demonstrate that the low fillet radii have a higher contact area and exhibit low current density, low contact pressure, and low stress, which is more reliable and efficient. This study will be highly beneficial for relay and circuit breakers manufacturers.