Thermal analysis of hermetically sealed electromagnetic relay in high and low temperature condition

Hermetically sealed structure is the optimal style to protect electromagnetic relay (EMR) from formidable working environment. Each product shall be subjected to thermal environment shock in accordance with MIL-STD-202 from -65'C to +125'C temperature, so it is of great importance for thermal analysis of EMR to increase the thermal stability and reliability requirement. In this paper, special finite element analysis (FEM) software ANSYS, was used for the accurate simulation of the internal relay structure. The elevated temperature characteristic of relay is investigated considering comprehensive thermal conductivity and convection effect. Internal complex heat transfer paths of EMR are determined and the influence of different temperature condition of inert gas on thermal performance is also researched. The results of the analysis can be useful for reliability thermal design of hermetically sealed EMR.