基于相位跟踪反馈控制的光纤GIS局放超声检测

Intelligent acousto-optic detection of GIS defects based on phase tracking feedback control

为实现对气体绝缘开关设备(GIS)的局部放电超声光学稳定检测,根据Michelson干涉原理构建GIS局部放电超声传感系统,设计一种可增强相位跟踪反馈抗干扰性能的新方法。在GIS设备上开展了干扰测试,构建得到能满足现场GIS局部放电超声检测要求的传感系统。研究结果表明:该方法可对低于1.8 kHz低频噪声造成的相位衰落起到明显的抑制效果。根据相位衰落抑制效果测试结果,设置相位反馈控制,传感系统达到40 mV的稳定幅值,保证光纤传感系统在100 Hz电动力干扰的条件下依然保持良好的稳定性。GIS局放检测试验结果显示,10 s内Michelson光纤干涉系统对局部放电超声信号达到精确检测的效果,压电传感器(PZT)未检测到局部放电的信号。该研究具有较好的实际应用价值,易于推广。

In order to detect the local emission ultrasonic optical stability of gas insulated switch(GIS),a GIS partial discharge ultrasonic sensing system was constructed based on Michelson interference principle,and a new method was designed to enhance the anti-interference performance of phase tracking feedback.The interference test is carried out on GIS equipment,and the sensor system which can meet the requirements of GIS partial discharge ultrasonic detection is constructed.The results show that the proposed phase feedback control method can significantly suppress the phase fading caused by low frequency noise below 1.8 kHz.Test results of phase fading suppression effect.After setting phase feedback control,the sensing system reaches a stable amplitude of 40 mV,ensuring good stability of the optical fiber sensing system under the condition of 100 Hz electrodynamic interference.The results of GIS local discharge test show that the Michelson optical fiber interferometer system can accurately detect the ultrasonic signal of partial discharge within 10 seconds,while the piezoelectric sensor(PZT)sensor can not detect the signal of partial discharge.This research has good practical application value and is easy to be popularized.