Micromachined Electric-Field Sensor to Measure AC and DC Fields in Power Systems

Micromachined Electric Field Mill Employing a Vertical Moving Shutter

“…Since the sensor output current is proportional to working frequency, at 7kHz operation sensor output is ~1pA. This is similar in performance to the device of [7], when scaled with electrode area. It should be mentioned that higher output current can be easily obtained by connecting multiple actuators in parallel, thus, effectively increasing the collection area for the entire sensor array.…”

“…Horenstein et al was the first to demonstrate such an MEFM [3]. Thermal actuation has been used by various groups to reduce the drive signal interference from the voltage needed to actuate the shutter in [6][7]. In 2009, Wijeweera et al demonstrated an MEFM using a thermally actuated resonant shutter [7], and a sensitivity of 42 V/m was achieved.…”

“…According to the shutter movement direction, the MEFMs introduced above can be divided into two categories: lateral movement [3][4][5][6][7] and vertical movement [8,9]. Lateral movement shutters usually suffer from the displacement of the shutter under strong electric field, which can affect and reduce the sensitivity.…”

Touchless capacitive sensor for hand gesture detection

“…4. These blocks are: current sense amplifier [10]; a synchronous demodulator including a phase shifter and a switch; and a filter for converting the amplitude of demodulated signal into a DC signal.…”

Torsional Moving Electric Field Sensor with Modulated Sensitivity and without Reference Ground

“…Rotating electric field mills are commonly used for dc field measurements, however, they are expensive and require frequent maintenance. MEMS field mills have been explored as solutions [5][6][7]. However, their shielding shutter is affected by high fields, leading to incorrect measurements.…”