An Electric Field Microsensor with Self-compensation for Sensitivity Drift

This paper proposes an electric field microsensor (EFM) with self-compensation for sensitivity drift. Different from previous ones, this proposed EFM sensitive structure mainly consists of sensing electrodes and reference electrodes, where the sensing electrodes are designed to measure the electric field, and the reference electrodes are used to monitor the movable structure vibration. According to the reference electrodes output information, the EFM can track the resonant frequency automatically by phase-locked loop circuit and compensate the sensing output signal in real time. Test results show that a linearity of 0.21 % and a total uncertainty of three round trips within 1.34% were achieved in the electric field range of ±18 kV/m. The EFMs' sensitivity drift was within 3.0% in the temperature range of -40~70 °C, showing a good self-compensation performance.