多层导电结构内部状态脉冲涡流检测分析方法  

Pulsed eddy current detection and analysis method for internal state of multi-layer conductive structure

作　　者：赵凌[1] 黄平捷[1] 刘宝玲[1,2] 赵树浩 侯迪波[1] 张光新[1] 

机构地区：[1]浙江大学控制科学与工程学院,浙江杭州310027 [2]南昌工程学院机械与电气工程系,江西南昌330000

出　　处：《浙江大学学报（工学版）》2016年第4期603-608,615,共7页Journal of Zhejiang University：Engineering Science

基　　金：国家自然科学基金资助项目(50505045;61174005);浙江省教育厅资助项目(Y201432539)

摘　　要：针对脉冲涡流多层导电结构内部状态检测问题及检测中提离抖动的干扰,采用Fisher线性判别分析(FLDA)进行脉冲涡流检测信号特征提取,抑制提离抖动的影响;应用支持向量机(SVM)进行多层导电结构内部状态的检测与分类;以双金属片温控器内部状态检测为实例进行实验验证.理论和实验分析表明,在多层导电结构内部状态检测时,FLDA可以通过选取最佳的投影方向,最大程度地分离有用特征信息和干扰信息,相较于基于峰值、峰值时间的时域特征法,能够有效地减小提离抖动的干扰,提高内部状态的检测准确度;在减小训练集样本的情况下,FLDA检测方法具有较高的检测准确率.Fisher linear discrimination analysis（FLDA）was used to extract signal features and restrain liftoff fluctuation in order to solve the problem of pulsed eddy current detection for internal state of multilayer conductive structure and the interference of probe lift-off.Then the support vector machine（SVM）method was investigated for multi-layer structure internal states automated classification.Detection for internal state of bimetallic temperature controller structure was taken as an example to validate the method by experiment.The theoretical and experimental results show that the proposed method FLDA can realize the maximum separation of the useful information and disturbance information by choosing the best projection direction.FLDA helps to restrain lift-off effect and obtain higher recognition accuracy compared with time domain feature extract method based on peak value and peak time.In the case of smaller sample size,the proposed method has a high detection rate.

关 键 词：脉冲涡流 多层结构 提离 Fisher线性判别分析(FLDA) 支持向量机(SVM) 

分 类 号：U28[交通运输工程—交通信息工程及控制]