摘要
脉冲涡流检测是当前金属材料无损检测主要的方法,激励电源作为系统中的关键部分,其性能将直接影响到检测结果。针对现有材料缺陷脉冲涡流检测方法中激励电源存在关断时间长、无恒流控制、功率小等问题,对非磁性材料的缺陷检测方法进行了研究,提出了一种新的脉冲电源电路,采用线性调整型恒流源,实现恒流与恒压钳位的复合电路拓扑结构。首先对线性单元进行闭环分析,证明了电路的可行性,再通过样机实证,验证了脉冲电源的稳定性和快速性。脉冲电源的幅值在20 A内可调,幅度误差小于1%,能够快速关断,下降时间可达纳秒级。最后利用该脉冲电源组成了一套脉冲涡流检测系统,并对铝合金进行了裂纹缺陷模拟检测实验。通过提取探测器峰值电压发现系统能够准确地识别不同缺陷深度,且具有较高的分辨率。
Pulsed eddy current testing is the main method of nondestructive testing of metal materials,and the performance of the excitation power supply as a key part of the system will directly affect the test results.In order to solve the problems of long shutdown time,no constant current control and low power of the excitation power supply in the existing material defect pulse eddy current testing methods,an investigation of defect detection methods for non-magnetic materials was conducted and a new pulse power supply circuit was proposed,which adopted a linear adjustment constant current source to realize the composite circuit topology of constant current and constant voltage clamping.Firstly,the closed-loop analysis of the linear unit is carried out to prove the feasibility of the circuit,and then the stability and rapidity of the pulse power supply are verified by the prototype demonstration.The amplitude of the pulse power supply is adjustable within 20 A,and the amplitude error is less than 1%.It can be shut down at high speed with a drop time in the nanosecond range.Finally,a pulsed eddy current testing system was built using the pulse power supply,and crack defect testing experiments were carried out on aluminum alloys.By extracting the peak voltage,it is found that the system can accurately recognize different defect depths with high resolution.
作者
文双
陈文光
刘之戬
郑亮
WEN Shuang;CHEN Wenguang;LIU Zhijian;ZHENG Liang(School of Electrical Engineering,University of South China,Hengyang,Hunan 421001,China)
出处
《南华大学学报（自然科学版）》
2024年第3期70-78,共9页
Journal of University of South China：Science and Technology
基金
国家重点研发计划项目(2018YFE0303103)。
关键词
缺陷检测
脉冲涡流检测
脉冲电源
恒流源
钳位电路
defect testing
pulsed eddy current testing
pulsed power supply
constant current source
clamping circuits
