压电阻抗损伤识别温度影响的协整消除方法研究  

Cointegration approach for the temperatur eeffect compensation in EMI damage detection

作　　者：李秀娟[1] 屈文忠[1] 肖黎[1] LI Xiujuan;QU Wenzhong;XIAO Li(Department of Engineering Mechanics,Wuhan University,Wuhan 430072,China)

机构地区：[1]武汉大学工程力学系

出　　处：《振动与冲击》2019年第18期128-134,共7页Journal of Vibration and Shock

基　　金：国家自然科学基金(51378402)

摘　　要：近年来结构健康监测与损伤识别研究中广泛采用压电高频机电阻抗方法(EMI)。由于环境温度变化也会使阻抗谱产生频移和幅值变化,甚至淹没结构损伤对阻抗谱的影响,造成损伤误报。因此提出了一种基于协整处理阻抗谱的方法,以消除长期监测过程中环境温度变化的影响。分析了阻抗谱中协整向量的构造原理,利用ADF检验和Johansen检验确定其不平稳阶数,将温度变化影响下不平稳的阻抗谱峰值频率时间序列协整为一个平稳的余量序列。利用压电片高频主动激励进行了钢板在温度变化工况下模拟损伤的EMI检测识别实验。实验结果表明,结构损伤导致平稳的协整余量序列发生突变,准确表征了结构损伤的发生,验证了阻抗谱协整处理环境温度变化方法的有效性。In recent years,the piezoelectric high-frequency electromechanical impedance method(EMI)has been widely used in the research of structural health monitoring and damage detection.Due to the environmental temperature variation,in the impedance spectrum,the frequency shift and amplitude variation,will usually occur,resulting in false diagnosis.The cointegration method was introduced to eliminate the temperature effects.The ADF test and Johansen test were used to determine the degree of non-stationary and cointegrate the non-stationary peak frequency series of the temperature influenced impedance spectrum into a stationary residual series.The EMI detection experiment for simulating the damage of a steel plate under a temperature varying environment was carried out by using the high-frequency active excitation of the piezoelectric sensor.The experimental results show that the structural damage leads to a sudden change in the cointegrated residual series,and its occurrence can be accurately characterized.

关 键 词：结构健康监测 压电阻抗方法(EMI) 环境温度 时间序列 协整 

分 类 号：TH212[机械工程—机械制造及自动化] TH213.3