PD Positioning of Electrical Transformers Based on the Designed Pressure-balanced EFPI Sensor Array

Extrinsic Fabry-Perot interferometric (EFPI) fiber-optic ultrasonic sensor, for its advantages, has been widely concerned in partial discharge (PD) detection. In this paper, a novel structure of EFPI sensor is proposed to achieve built-in detection in power transformers. A unique sensor array and installation position are specially designed for built-in detection. Based on the sensor array, steered response power (SRP) algorithm and time difference of arrival (TDOA) algorithm are combined to give a more accurate positioning result. The experimental result shows good positioning accuracy, which illustrates the feasibility of the designed sensor array and optimized algorithm.