Location method for PD ultrasonic signal in long high-voltage cables based on optical fiber sensing technology

It proposes to solve the problems of polarization attenuation and phase drift in distributed optical fiber sensing system, and improve the positioning accuracy of partial discharge signal in high-voltage cables. An optical fiber sensing detection system model based on an improved polarization control algorithm was established by analyzing the ultrasonic characteristics of partial discharge in cables. Polarization controller driving voltage control module is designed to reduce polarization attenuation. The algorithm’s attenuation rate, noise amplitude, control accuracy and other parameters were simulated based on the improved Adamax algorithm, which shown the average iteration time reduces by 35.91 %, and the control convergence accuracy is 10-4 level. Then, an optical fiber detection system of partial discharge in high voltage cable is established, and the experimental results show that the locating accuracy based on the improved polarization control algorithm is less than ± 12 m in a 15 km high voltage cable. The reliability and locating accuracy of the polarization controller and the improved algorithm in the distributed optical fiber sensing system are verified. There, detection method above can be extended to test state perception of high-voltage transmission equipment.