摘要
常规多频阻抗分析仪一般采用复杂的硬件电路设计进行多频激励合成、多频信号分离及频谱分析,其结构设计复杂,生产成本较高且检测分辨率和可靠性较低。该文设计了一种用于涡流检测的高性能的多频阻抗分析系统,它采用以DSP为核心构造的检测系统产生多频激励信号并最小化其峰值因数,应用软件方法对激励电流和感应电压做FFT变换和交叉频谱分析获取各谐波分量下的传感器阻抗信息,从而有效地实现参数分离和干扰抑制。选用双电感网络和U型铁芯传感器两种方式进行试验,结果表明该系统测量精确度和可靠性高,稳定性好,为研制智能化多频阻抗分析仪提供了良好的基础。
Conventional multi-frequency impedance analyzer usually adopts complex hardware circuit design to accom- plish multi-frequency excitation waveform composition,multi-frequency signal separation and spectral analysis.The structure design was complex,production costs was high and detection resolution and reliability was low.This paper proposes the design of a high-performance multi-frequency impedance analyzing system（MFIA） for eddy current test- ing.The DSP-based detecting system generates multi-frequency excitation waveform with minimum crest factor,imple- ments FIeF cross-spectral analysis of the excitation current and sensing voltage with software method to obtain sensor impedance in different harmonic components,which can separate parameters and suppress interferences effectively. Two-inductor network and U-cored eddy current sensor were fitted onto the circuit system respectively to carry out experiments.The results show that the system possesses a high detection resolution and reliability as well as good stability,which provides a favorable basis for designing intelligent multi-frequency impedance analyzer.
出处
《自动化与仪表》
北大核心
2013年第6期49-52,56,共5页
Automation & Instrumentation
基金
江苏高校优势学科建设工程资助项目(苏财教[2011]8号)
