Research on Thermal Aging Mechanism and Methods for Improving Electrical Performance of PCBs in Substation Sensors

Printed circuit boards (PCBs) are usually the key areas of sensor failure in substations. Therefore, it is necessary to study the methods for improving the electrical performance of PCBs after thermal aging. Three typical interconnection structures of PCBs are extracted in this article. The mechanism that how the thermal aging affects the electrical performance of PCB interconnection structures is experimentally studied. Furthermore, the methods to improve the electrical performance of PCBs after thermal aging are proposed. The results indicate that thermal aging can gradually degrade the surface materials of PCBs, resulting in flocculent pits and material layering, reducing their insulation performance and causing a decrease in flashover voltage of about 20% to 25%. By optimizing the parameters of typical interconnection structures, the electrical performance of PCBs after thermal aging can be improved, and the maximum flashover voltage can be increased by about 40%.