Experimental and numerical analysis of the influence of the contact resistance in a high-power fuse on its time-current characteristic

This paper presents a study of thermal processes and time-current characteristics of a high-power low-voltage fuse at normal and increased contact resistance. Experimental and numerical studies have been performed. The experimental studies have been carried out by means of an experimental setup, especially developed for the purpose. Temperature measurement has been realised both by a contact thermometer and by a thermovision camera. The finite element method has been used in the numerical study. A computer model of the fuse has been developed in the software product COMSOL. The model reads the thermal processes in the fuse, as well as the heat transfer to the environment, which occurs by radiation and convection. Results about the influence of the contact resistance on the fuse heating and its time-current characteristic have been obtained. The obtained experimental and numerical results have been compared.