Experimental and theoretical study of heat transfer in switches

The Finite Element Analysis (FEA) technique is applied to the thermal analysis of AgCdO contacts under high intensity arc conditions. FEA uses the axisymetric mode for modelling, with adjoining material boundaries combined within the model using Boolean Algebra Commands. The validity of the model is examined against the measured data in a special case where the arc power is distributed equally to the contacts. The measured data is the temperature which is taken from the output of a thermocouple placed 240 /spl mu/m away from the surface of the contact. The paper also investigates the erosion characteristics of the contacts by varying thermal conductivity, specific heat capacity and density of the materials.