We have developed a highly sensitive electric-field sensor with novel comb-shaped microelectrodes. The sensor is based on modulating an incident field with a grounded shutter and measuring the induced charge of sensing electrodes. Owing to the shutter covering the side wall of the sensing electrodes, the fringing fields are no longer a factor that reduces the performance of the sensor. Moreover, in order to improve the efficiency of the charge induction, comb-shaped microelectrodes are introduced. The sensor can measure not only electrostatic field, but also AC field. Tested in ambient air conditions, the minimum detectable field of the sensor is approximately 40V/m with an uncertainty of 1% in DC electric field range 0-50kV/m and 10V/m for a 50Hz AC field. Finally, the use of the sensor to detect ice accretion on high power electric cables is achieved.

To improve the sensitivity and stability, a novel mode-localization resonant MEMS (Micro-Electro-Mechanical System) electric field sensor based on closed-loop feedback is presented in this paper. The sensor is based on the principle that the mode localization effect can dramatically increase the sensitivity of a resonant system. Moreover, in order to detect the electric field in real-time and improve the resolution and stability of the sensor, closed-loop feedback is introduced. One of the output signals of the sensor is fed back to the input port, where the output signal has been processed by a phase-locked loop part and automatic gain control part. This paper analyzes amplitude-frequency characteristics, phase-frequency characteristics, sensitivity, and output characteristics by modeling, theoretical calculation, and finite element simulation. The device prototype is fabricated based on SOI process. Tested in vacuum conditions, the minimum detectable electrostatic field of the sensor is better than 10V/m, the accuracy of the sensor is 5.3%, and the repeatability is 0.56%.

High-altitude electric fields are a critical parameter of electricity in the atmosphere. Due to such drawbacks as their bulk and high cost, traditional electric field mills are not available for daily atmospheric sounding purposes. This paper introduces a highly sensitive and robust electric field sounding sensor based on an existent micro-electro-mechanical systems chip and a new protective package that augments sensor sensitivity. To gain high sensitivity, an innovative external metal electrode connects to the electric field microchip's package cap, hangs down out of the guardian foam, and effectively enhances the local electric field near the microchip due to the distortion effect. This distortion regularity was studied during a series of finite element simulations, calibrations, and comparison experiments. With a 1.5-meter-long external electrode, the sensitivity of the sensor reached 465 mV/kV/m with a resolution that was better than 10 V/m in an actual long-term ground comparison test. Furthermore, the microsensor chip and its circuit are protected inside a foam while the metal electrode is exposed outside, therefore gaining a robust stability during harsh environments such as low temperature, rainfall, etc. To examine the performances, we built an electric field sounding system, including the electric field sensor, a radiosonde, and a receiving antenna, and measured high-altitude electric fields in various weather conditions. Intended for atmospheric electricity research, our innovative electric field sounding sensor would be especially propitious if integrated with a radiosonde and applicable to daily sounding services.

This paper presents a novel atmospheric electric field sensor based on high sensitivity resonant MEMS (microelectromechanical systems) electric field sense chips, which resolves the problems of motor wear, high power consumption and failure rate of the conventional electric field mill. The chip was fabricated in a commercial SOIMUMPS process. The sensor overall structure scheme was proposed and the phase-sensitive detection method was used for extract the chip output signal. A special protective structure was designed for protecting the sensor against the influences of the external environment. The minimum detectable electric field of the sensor is 10V/m with an uncertainty of 0.67% in the range of 0~50kV/m, and its power consumption is only 0.62w. The outdoor test showed that the plotted data of the sensor agreed well with those of the conventional electric field mill on both sunny day and thunderstorm day, which indicates that the developed sensor can meet the applications of lighting hazard warning.

Based on the resonant electric field microsensors with coplanar electrodes, a novel non-intrusive measurement scheme of DC power-line voltage suitable for actual product is presented in this paper. Compared with using microsensors directly without some protection, employing the proposed scheme can avoid the influence of humidity and electromagnetic disturbance on non-contact voltage measurement. A theoretical model is developed to analyze the influence of the structural parameters of the proposed measurement scheme on its sensitivity and to predict the voltage response. Furthermore, the theoretical analysis reveals that the proposed scheme obtains the DC power-line voltage non-intrusively by measuring the voltage of a floating electrode. A prototype of the non-intrusive measurement apparatus of DC power-line voltage has been developed, calibrated, and tested. The prototype shows a favorable linear response characteristic with a linearity of 0.86%. And the experimental results are in good agreement with the theoretical results. The maximum relative deviation noticed is −2.16% over a range of voltages from −1000 V to 1000 V.