A novel detection method and targets signal extraction algorithm for parallel steel pipeline localization and defects recognition based on harmonic magnetic field are proposed. An orthogonal vector differential focusing array detector was designed, which radiates high-frequency (HF) and ultra-low-frequency (ULF) electromagnetic waves to pipeline based on the principle of Frequency Modulated Continuous Wave (FMCW), and records the signals in parallel using high-sensitivity Tunnel Magneto Resistance (TMR) array sensors. The joint signal pre-processing algorithm of Combination Morphological Pulse Elimination (CMPE) and Quantum Genetic Gaussian Potential Stochastic Resonance (QGGPSR) is proposed to improve signal quality by adaptively eliminating random pulse and noise. The time–frequency analysis algorithm Complementary Ensemble Local Mean Decomposition (CELMD) is used to decompose the pipeline defects signal in detail, and the appropriate components are selected and fused into a correlation array signal cluster. Finally, the targets signal are separated by Limited-memory BFGS Independent Component Analysis (L-BFGS-ICA) based on machine learning optimization to enhance their legibility. The magnetic dipole harmonic simulation model and the 20# steel parallel pipeline experimental platform are established, and compared with the passive detection method to verify the effectiveness and practicality of the proposed method. The results show that this method can accurately locate parallel pipelines and detect different kinds of defects in noisy environment, which is of great significance for the application of non-contact Non-Destructive Testing (NDT) in practical engineering.

提出了一种基于谐波磁场的平行钢管定位与缺陷识别的新方法和目标信号提取算法。设计了一种正交矢量差分聚焦阵列检波器，它基于调频连续波原理，向管道辐射高频电磁波和超低频电磁波，并并行记录信号。使用高灵敏度的隧道磁阻（TMR）阵列传感器。提出了结合形态学脉冲消除（CMPE）和量子遗传高斯势能随机共振（QGGPSR）的联合信号预处理算法，通过自适应消除随机脉冲和噪声来提高信号质量。时频分析算法“互补集合局部均值分解”（CELMD）用于详细分解管道缺陷信号，然后选择适当的分量并将其融合到相关阵列信号簇中。最后，基于机器学习优化，通过有限内存BFGS独立分量分析（L-BFGS-ICA）分离目标信号，以增强其可读性。建立了磁偶极子谐波仿真模型和20＃钢平行管道实验平台，并与无源检测方法进行了比较，验证了所提方法的有效性和实用性。结果表明，该方法可以准确定位并行管道，并在嘈杂的环境中检测出各种缺陷，