Fault Diagnosis of Power Transmission Lines Using a UAV-Mounted Smart Inspection System

Fault diagnosis of power transmission systems (PTSs) is crucial for ensuring the reliability of power grids because most grids are exposed to harsh environments. For integrity diagnosis of PTSs, this article proposes a nondestructive patrol inspection method that employs a smart inspection system (SIS) mounted on an unmanned aerial vehicle (UAV). This system overcomes the geographical limitations faced in accessing PTSs. The SIS includes an ultraviolet camera system that can detect partial discharges on the damaged surfaces of PTSs. The SIS is characterized by three main features. First, it employs an automatic line-tracking method based on image-processing methods. Second, defect locations are automatically estimated on the basis of the consistency of partial discharges, where consistency indicates the steadiness of corona discharges in one-dimensional global coordinates. Third, an alarm is triggered on the basis of the combination of the result from a statistical outlier detection method and the estimated partial discharge locations on a two-dimensional partial discharge map. Finally, a UAV equipped with the proposed system is field-tested for PTS inspection in the autopilot mode. Field tests conducted on ultrahigh-voltage PTSs confirmed the damage detection capabilities of the proposed method and demonstrated its effectiveness and convenience.