Three-Phase Voltage Measurement System for Overhead Transmission Lines Based on Electric Field Integration Method

The accurate measurement of line voltage is of great significance for power calculation, overvoltage online monitoring and relay protection. According to the conservatism of the space electric field of the transmission line, the feasibility of measuring the line voltage by the electric field integration method is theoretically verified. Established a vertical line with transmission lines perpendicular to the ground as the integration path. Based on the characteristics of electric field integration, a non-contact electric field sensor was designed. The measurement of the output electric field signal of the sensor node was completed through the designed multi-channel synchronous acquisition circuit, and the real-time calculation, waveform display and analysis of electric field integration were achieved. A three-phase horizontally arranged transmission line test platform was built, and the measurement test of transmission lines with different voltages was carried out. The feasibility of the proposed electric field integration method is proved by simulation and experiment, which provides another measurement method and system for non-contact voltage measurement.