Modeling and experimental investigation of magnetic anomaly detection using advanced triaxial magnetoelectric sensors

Magnetoelectric (ME) sensors have been proven to have great performance on weak magnetic field detection with high sensitivity, low noise, broad bandwidth and low power consumption. In this work, a self-designed ME detection system consisting of a high-performance triaxial ME sensor was used for magnetic anomaly detection (MAD). As the core sensing element of the ME sensor, the laminated ME composites were made of Metglas laminates and Mn-doped PMN-PT single crystal fibers with in-plane series connection. The noise equivalent magnetic induction (NEB) of the ME sensors were below 6.28pT/Hz1/2 @ 1 Hz, and the limit detection of magnetic field is about 5 x 10-10 T, representing great performance to detect weak magnetic field. An experi-ment of detecting a real ship was conducted to test the performance of the triaxial ME detection system. To analyze the magnetic anomaly signal induced by the ship, a 3D finite element model (FEM) about the magnetic field distribution of the moving ship is developed. The estimated signals of the scalar total magnetic field and the motion parameters of the ship simulated by the proposed FEM match well with the experimental data, which proves the reliability of the model. The error analysis of the simulation was also discussed in detail. The experimental investigation reveals a promising application of ME sensor in MAD, while the proposed finite element model can be further modified to meet the analysis requirements on the detection of the magnetic anomaly induced by ferromagnetic targets with large dimension.