涡流检测中的可调带通滤波器设计  

Tunable bandpass filter design foreddy current detection

作　　者：高源 张志杰[1] GAO Yuan;ZHANG Zhijie(Key Laboratory of Instrumentation Science&Dynamic Measurement Ministry of Education,North University of China,Taiyuan 030051,China)

机构地区：[1]中北大学仪器科学与动态测试教育部重点实验室,太原030051

出　　处：《自动化与仪器仪表》2024年第4期206-210,215,共6页Automation & Instrumentation

摘　　要：涡流检测作为一种常用的金属表面缺陷检测方法,其一般包括单线圈激励、单线圈接收,单线圈激励、多线圈接收,或者多线圈激励、多线圈接收等几种检测方式。但是在同频激励下,接收线圈的信号通常很微弱并且伴随着很强的背景噪声,因此需要对采集到的接收线圈信号进行滤波处理。本文采用频带分段方式和多路复用思想,利用低噪声和低失真运放THS4011和THS4012分别设计了二阶无限增益多路反馈型(MFB)和二阶双运放型(DABP)两种可调频的有源带通滤波器。仿真和实验测试结果表明,所设计两种滤波器的通频带宽均为1 kHz~1 MHz,且均可实现在通频带范围内任意调节中心频率。二者均可适用于复杂涡流检测场景下不同的带通滤波需求。Eddy current testing is a commonly used method for detecting surface defects in metals,which generally includes several detection methods such as single-coil excitation and reception,single-coil excitation and multi-coil reception,or multi-coil excitation and reception.However,under the same frequency excitation,the signal received by the receiving coil is usually very weak and accompanied by strong background noise,so the received coil signal needs to be filtered.In this paper,a frequency band segmentation method and multiplexing idea are used to design two types of active bandpass filters with adjustable frequency using low noise and low distortion operational amplifiers THS4011 and THS4012,namely second-order infinite gain multiple feedback(MFB)and second-order dual operational amplifier(DABP)filters.Simulation and comparative experimental results show that the bandwidth of the designed filters is 1 kHz~1 MHz,and the center frequency can be adjusted arbitrarily within the bandwidth.Both can be applied to different bandpass filter requirements in complex eddy current testing scenarios.

关 键 词：涡流检测 有源滤波器 可调带通滤波 无限增益多路反馈 双运放 

分 类 号：TP214[自动化与计算机技术—检测技术与自动化装置]