Development of PD Detection Technique of Overhead distribution lines using UHF and ultrasonic

In order to improve the accuracy and efficiency of partial discharge (PD) detection on overhead distribution lines, this paper presents a method of PD detection on overhead distribution lines based on ultrasonic and ultrahigh frequency (UHF). By analyzing the propagation characteristics of ultrasonic and UHF signals, an inversion formula of PD intensity is established, which can accurately eliminate the influence of detection distance on the accuracy of PD detection. According to the difference of ultrasonic velocity and UHF signal velocity, a method of calculating PD defect distance based on statistics was proposed to provide a new reference for the defect location of covered conductor lines and improve the inspection efficiency. Then, the algorithm design scheme based on the above method is introduced in detail. Finally, a test platform was built in the laboratory to test and analyze the common defect model of overhead line, and the effectiveness of the method proposed in this paper was verified.