Thermal stress and electrical contact reliability analysis of tulip contacts in circuit breaker

In the context of prolonged operation, the tulip contacts of circuit breakers are susceptible to structural looseness due to electromagnetic and environmental vibrations, which, when compounded by surface oxidation, can diminish electrical contact performance. This study aims to investigate the contact reliability of circuit breaker tulip contacts by developing a three-dimensional finite element simulation model that integrates electrical, force, and thermal analyses. The research examines the variations in pressure, electrical contact, and contact temperature rise of the tulip contact, as well as their interplay. It also delves into the temperature field and structural thermal stress distribution of the tulip contact under steady-state conditions and investigates the stress and deformation changes across different temperatures. Modal analysis is conducted to ascertain the natural frequencies and vibration modes of the tulip contact within the first six modes, and the impact of the number of contact fingers on modal characteristics is explored. The findings offer theoretical insights for the structural optimization and manufacturing of circuit breaker tulip contacts, thereby enhancing their operational reliability.