基于EFPI传感器的GIS局部放电模式识别研究

非本征法布里-帕罗干涉(EFPI)光纤超声传感器可用于气体绝缘全封闭组合电器(GIS)内部的局部放电超声信号检测及模式识别研究,相较于传统的压电式传感器,具有灵敏度高、抗干扰能力强等优点。基于此,文中在充有0.4 MPa SF₆气体的GIS腔体内设置尖端、金属颗粒、悬浮和沿面4种典型的局部放电模型,创新性地利用EFPI传感器对放电超声信号进行检测,提取单次超声脉冲信号波形特征形成特征参数数据库,分别应用概率神经网络(PNN)算法和支持向量机(SVM)算法进行模式识别并比较分析。EFPI传感器检测到的超声信号特征突出,在提取特征参数的基础上,2种模式识别算法均能达到85%以上的平均识别率,且SVM的识别效果要优于PNN。

Partial discharge pattern recognition in GIS based on EFPI sensor

The extrinsic Fabry-Perot interferometer (EFPI) optical fiber ultrasonic sensor can be used for the detection and pattern recognition of the partial discharge ultrasonic signal inside the gas-insulated switchgear (GIS). Compared with the traditional piezoelectric sensor, it has many advantages such as high sensitivity and strong anti-interference ability. Based on this, four typical partial discharge models of tip, metal particles, suspension and quay are set in the GIS cavity filled with 0.4 MPa SF₆ gas. The EFPI sensor is used to detect the discharge ultrasonic signal. The waveform characteristics of a single ultrasonic pulse signal are extracted to form a characteristic parameter database, and the probabilistic neural network (PNN) algorithm and the support vector machine (SVM) algorithm are respectively used for pattern recognition. The recognition results of the two algorithms are compared and analyzed. The ultrasonic signals detected by the EFPI sensor have outstanding features. Based on the extraction of feature parameters, the two pattern recognition algorithms can achieve an average recognition rate of over 85%, and the recognition rate of SVM is higher than that of PNN.