Assessment of novel material concepts for high voltage arcing contacts by use of finite element analysis

The classical design of high voltage arcing contact systems makes use of the tungsten-copper (WCu) composite material in the contact region. During switching operation the arcing results into severe thermal and mechanical loading of the arcing contact system. Whereas WCu is noted to be the reference arcing contact material in medium and high voltage switches the substitution of WCu by carbon fiber reinforced carbon (CFC) composite materials may show a beneficial effect on the mechanical, thermal, and electro-magnetic properties of the contact system. In particular, the nearly temperature independent mechanical stiffness and strength of the CFC material at a low density together with high thermal and electrical conductivity seems promising for use in arcing contact systems. A finite element based concept study is done aiming at verifying the potential of a commercially available CFC material compared to WCu with regard to the application in high voltage switches under different loading conditions.