Novel Voltage Distortion Measurement Method Using a Contactless Electric-Field Sensor Array

A contactless measurement method is designed for detecting overhead-line voltage distortion. This method uses three single-axis electric field (EF) sensors to be placed on the ground plane below the measured overhead line. Moreover, EF sensors are spread out in a straight and cross the overhead lines. Besides, the EF sensors are used to sense the space electric fields. With the geometric specifications of the overhead transmission line obtained from utilities, the proposed method can accurately determine the voltage harmonic distortion of each phase for the overhead line.