Design of an integrated conformai partial discharge senor for inspection robot used in substations

Intelligent inspection robot are gradually used for daily online inspection in substations of State Grid Corporation of China and China Southern Power Grid recently, which improves the intelligence level of the power system. The introduction of partial discharge (PD) detection into intelligent inspection robot with high definition image and infrared image sensors would give a greater degree of expansion of detection function and find insulation defects of power equipment in substations more efficiently. Considering the structure of the common inspection robot and requirements of PD detection in substations, this paper designed an integrated conformal PD sensor. This PD sensor includes a high-gain directional ultra-high frequency (UHF) antenna and an omnidirectional ultra-wideband (UWB) antenna, which could be installed in the lashing board above inspection robot's image camera, to realize the integrated conformal design. Ansoft HFSS software is used for building antenna model, simulation and optimization of the antenna performance. The proposed PD sensor offers the following flexibilities through simulation results: the high-gain directional UHF antenna has a good directional symmetry, less sidelobes and its average gain is up to 5 dBi in detection direction over the working frequency range, the small size omnidirectional UWB antenna allows easy installation achieving a working bandwidth (VSWR<;2) of 9-times frequency multiple and good radiation properties in the whole working bandwidth.