用于油中局部放电检测的Fabry-Perot光纤超声传感技术

Fabry-Perot Optical Fiber Ultrasonic Sensing Technology for Detection of Partial Discharge in the Oil

高压电气设备中局部放电(PD)的光学检测方法是具有多重优势的新型检测方法,它灵敏度高,不受电磁干扰(EMI)的影响,有着高强度的绝缘性能。为此,介绍了基于Fabry-Perot(F-P)干涉法的F-P光纤超声检测系统的特点和原理,制作了局部放电模型,并使用F-P光纤传感器与压电陶瓷(PZT)传感器进行了联合检测。试验验证了F-P光纤传感器检测的局部放电信号幅值与局部放电量的关系,并研究了不同检测角度下F-P光纤传感器检测的局部放电信号响应。结果表明:F-P光纤传感器可以有效地检测到局部放电信号,有较高的检测灵敏度;F-P光纤传感器检测的局部放电信号幅值与局部放电量在一定范围内有着正相关关系;该F-P光纤传感器能够检测到全角度的局部放电信号。因此,F-P光纤传感器可以很好地应用在高压电气设备的状态监测中。

Optical fiber sensor represents a novel technology for detecting partial discharges （PD） in high voltage elec- trical equipment. We introduced the features and principles of a detection system developed with optical sensors based on Fabry-Perot （F-P） interferometry. We built a partial discharge model, and detected it with optical fiber F-P sensors and piezoelectric （PZT） sensors together. Through the experiments, we found the relationship between the ultrasonic ampli- tude obtained by sensors and the discharge magnitude, and also studied the signal response of optical fiber F^P sensors at different detection angles. The experimental results show that optical fiber F-P sensor can detect PD from a long distance with high sensitivity. The signal amplitude from optical fiber F-P sensors is positively related to PD magnitude. Plus, opt- ical fiber F-P sensor is able to detect PD at all angles. Hence, it is concluded that optical fiber F-P sensor is promising for applications in monitoring high voltage electrical equipment.