数字锁相放大技术在场指纹法中的应用

Application of Digital Lock-in Amplifier Technique to Field Signature Method

针对传统场指纹法(FSM)系统的直流激励电流的幅值较大的问题,提出了将锁相放大技术应用到FSM中以减小激励电流的方法。通过试验对比了传统FSM激励电流和采用锁相放大技术的激励电流的幅值。结果表明,在满足测量精度的前提下,锁相放大技术可以大幅度减小FSM的激流电流,系统能对管道内部腐蚀情况进行高效、可靠的在线监测。

To overcome the problem that the amplitude of excitation direct current （IX;） is too large m tracimonal field signature method （FSM）, a method for aspplication of digital lock-in amplifier technique to FSM was proposed. The results showed that digital lock-in amplifier technique could significantly reduce the amplitude of excitation current under the premise of meeting the measurement accuracy in comparison with traditional FSM excitation current, the system could provide efficient and reliable on-line monitoring and evaluation of the inner corrosion of pipelines.