Proximity coupled interdigitated sensors to detect insulation damage in power system cables

Proximity coupled interdigitated sensors are introduced to detect insulation damage in power system cables. A new empirical model for interdigitated sensors with conducting backplane is developed. The validity of this newly proposed model is verified by comparing the results obtained from the new model with simulation and experimental results. It is shown that while the existing models fail to correspond to the simulation and experimental results due to the presence of the conducting backplane, the new model can fairly approximate the effect of the backplane on the sensor performance. A meander and a quarter-circular sensor are designed for insulation damage detection. Measurement results on planar dielectric materials, as well as practical power line cables are presented to demonstrate the usefulness of these sensors. Such sensors placed on microrobots crawling along power cables could lead to the potential autonomous monitoring of an electric power system.