Influence of low temperature conditioning on the electrical and mechanical properties of dielectrics

A wide variety of power apparatus in service are exposed to several types of adverse environmental conditions of which one of them is low temperatures. The insulating materials employed in power apparatus should perform satisfactorily at these temperatures for reliable operation of overall units. Insulating materials like polypropylene, cross linked polyethylene, medium density polyethylene and polyvinyl chloride are identified and are subjected to various low temperatures below ambient. The electrical and mechanical properties of insulating materials like volume resistivity, surface resistivity, polarisation index, tensile strength etc., are studied with respect to low temperatures.<>