Temperature monitoring in high-power electrical contacts using thin-film sensors

Due to the increasing demand for higher voltage levels and currents in electrical applications, the quality of the electrical connection is of great importance. Poor electrical contacts show excessive heat generation, which goes hand in hand with lower efficiency of the electrical contact. In electrical high-power applications temperature monitoring is necessary to detect faulty behavior and excessive heat to prevent further harm to the electrical system. To address this need, a thin-film sensor system was developed to measure the temperatures of the contact spots in a high-power charging system based on face-contact technology during the charging process. With a spatial resolution of 1.5 mm², six thin-film temperature sensors were positioned at distances of 5.5 and 15.5 mm from each contact spot. The dielectric strength of the thin film system was evaluated and temperature measurements in a test setup were performed. The sensors showed low latency to Joule heating in the electrical connection.