Investigation of heat-of-fusion heat sinks for polymer-type metal oxide surge arresters

Heat sinks are employed in many types of surge arresters when needed to attain the desired thermal stability. The low thermal conductivity of the polymer housing of polymer-type surge arresters increases the need for such heat sinks, which reduce the ZnO element temperature after fault-current-induced heating and thereby reduce subsequent power dissipation at rated AC voltage. Heat-of-fusion heat sinks, which contain a material that melts at low temperature to absorb heat at a constant, low temperature can "clamp" the ZnO temperature and increase arrester thermal stability.