The measurement of the surface charge on the insulating dielectrics is critical to estimate the insulation strength of electrical equipment in operation. Unavoidable interactions with the electromagnetic field, however, generally result in distortion measurement of active sensor. Thus, it is of great significance to investigate a passive sensor for monitoring the deposited charge. Here, a passive optical fibre electrostatic sensor is developed on the principle of Fabry–Perot interference to quantify the surface potential of the insulating dielectrics. The sensitivity of quantifying the electrostatic charge is explored in terms of the wavelength shift in the interference spectrum, and the linear correlation is 0.99. Meanwhile, the sensor can identify a negative quadratic trend with the increase of the surface roughness of the insulating dielectrics. The merits of the proposed sensor such as passive monitoring, bipolar electrostatic detection, and the excellent ability of anti-electromagnetic interference are highlighted in the results. Hence, this sensor can serve as an effective tool to monitor the electrostatic charge in the fields of smart electrical equipment, fuel transportation, aerospace, integrate circuit etc.

中文翻译：

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基于法布里-珀罗干涉法的无源光纤传感器，用于绝缘电介质的双极静电监测

绝缘电介质表面电荷的测量对于估计运行中电气设备的绝缘强度至关重要。然而，不可避免的与电磁场的相互作用通常会导致有源传感器的测量失真。因此，研究用于监测沉积电荷的无源传感器具有重要意义。这里，根据法布里-珀罗干涉原理开发了无源光纤静电传感器，以量化绝缘电介质的表面电势。通过干涉光谱中的波长偏移来探讨静电荷量化的灵敏度，线性相关性为0.99。同时，随着绝缘电介质表面粗糙度的增加，传感器可以识别出负二次趋势。结果凸显了所提出的传感器的优点，例如无源监测、双极静电检测以及出色的抗电磁干扰能力。因此，该传感器可以作为智能电气设备、燃料运输、航空航天、集成电路等领域静电荷监测的有效工具。