Research on AC and DC Hybrid Electric Field Sensing for Power Distribution Grid

Electric field is an important physical quantity that reflects whether the lines or equipment of the distribution network are live or not, and whether the maintenance personnel enter the dangerous live area. With the development of AC and DC distribution networks, it is of great significance to research an AC/DC hybrid electric field sensor that can sense both AC and DC electric fields. In this paper, based on the electrostatic driven MEMS electric field sensor, the demodulation algorithm of AC electric field and DC electric field is designed. In order to solve the problem that MEMS electric field sensor is affected by the space charge accumulation effect, a differential sensor structure design is proposed to eliminate the impact of charge accumulation on electric field measurement. The back-end circuit of the sensor is designed to complete the power supply, signal amplification and communication functions for the MEMS electric field sensor chip,finally, the test results show that the designed sensor has good linearity.