提出了一种用于双芯电线电流监测的自全式电流传感器。该传感器由霍尔元件、信号调理模块、无线传输模块、采能线圈及电源管理电路组成,实现对载流双芯电线的自供电无线电流传感。霍尔元件传感载流线周围产生的磁场实现电流监测,线圈感应磁场产生电输出,经过电源管理为传感器供电。根据双芯电线电流产生的磁场分布特点,采用非对称磁芯结构设计,形成具有不同磁通的磁回路,低通量支路用于传感,较高通量支路用于能量采集。实验表明该传感器能够自供电实现对双芯电线1 A以上电流的传感,灵敏度为1.47 m V/A。
A passive current sensor,consisting of SmFe_(2)/PZT/SmFe_(2)self-biased magnetoelectric(ME)composite and Fe_(73.5)Cu_(1)Nb_(3)Si_(13.5)B_(9)nanocrystalline flux concentrator for weak current detection at power-line frequency,was fabricated and characterized.Giant magnetostrictive material of SmFe_(2)plate with large anisotropic constant provides a huge internal anisotropic field to bias the ME transducer in closed magnetic loop.Consequently,the additional magnetomotive force induced by the internal field and the corresponding increased effective permeabil-ity contribute to the improvement of the sensitivity.Experimental results demonstrate that the presented sensor has a higher sensitivity of 152 mV·A^(-1)at 50 Hz with a slight nonlinearity of~0.01%full scale(FS)and matches well with the predicted value.This presented current-sensing device exhibits approximately 2.3 times higher sensitivity than that of conventional ME composite with[Pb(Zr_(0.48),Ti_(0.52)O_(3)](PZT)and Terfenol-D plates serving as a key sensitive component.In addition,time stabilities of the presented sensor were evaluated for a long period of 72 h and analyzed through mathematical statistics method,and favorable stabilities with an uncertainty of 0.5μV are obtained in continuous 1 h testing.These results provide a significant advancement toward promising application of the tri-layer self-biased ME laminate for power-line elec-tric cords monitoring.
We comparatively investigate the influence of various high-permeability alloys on the hysteretic and remanent resonant magnetoelectric(ME) response in a composite of magnetostrictive nickel(Ni) and piezoelectric Pb(Zr1-x, Tix)O3(PZT). In order to implement this comparative research, Co-based amorphous alloy(CoSiB), Fe-based nanocrystalline alloy(FeCuNbSiB) and Fe-based amorphous alloy(FeSiB) are used according to different magnetostriction(λs) and saturation magnetization(μ0Ms) characteristics. The bending and longitudinal resonant ME voltage coefficients(αME,b and αME,l)are observed comparatively for CoSiB/Ni/PZT, FeCuNbSiB/Ni/PZT, and FeSiB/Ni/PZT composites. The experimental data indicate that the FeSiB/Ni/PZT composite has the largest remanent self-biased αME,band αME,ldue to the largest magnetic grading of λs and μ0Ms in the FeSiB/Ni layer. When the number of FeSiB foils is four, the maximum remanentαME,b and αME,l at zero bias magnetic field are 57.8 V/cm·Oe and 107.6 V/cm·Oe, respectively. It is recommended that the high-permeability alloy is supposed to have larger λs and μ0Ms for obtaining a larger remanent self-biased ME responses in ME composite with high-permeability alloy.
