Wide-Range and High-Precision Magnetoelectric Current Sensor for Power Frequency Current Detection

Wide-range current sensors have extensive applications in power grid systems. Current sensing technologies predominantly rely on Hall-effect sensors, shunts, and transformers, which encounter technical challenges such as high-power consumption, intrusive measurement methods, elevated costs, and installation requiring outage, etc. In this work, we proposed a current sensor based on magnetoelectric coupling effect, which is made of the Terfenol-D/PMN-PT/Terfenol-D magnetoelectric composite. The proposed current sensor shows the resonance magnetoelectric coefficient of 21.32 V/(cm∙Oe) at 32.7 kHz, with the limit of detection (LOD) of 2.01 pT under resonance. Meanwhile, the linear range of the proposed sensor can be regulated by the DC bias magnetic field that provided by NdFeB permanent magnets. Due to the large magnetostrictive saturation of Terfenol-D, the proposed current sensor presents a large linear range for magnetic field detection. Also, the proposed current sensor has been verified to measure wide-range current from 0.8 mA to 1024 A, with a linear range spanning over four orders of magnitude, a sensitivity of 9.08 mV/A, and a nonlinearity error below 0.5 %FS, demonstrating significant potential in wide-range and high-precision current detection.