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Magnetoelectric (ME) sensors are widely studied and well suited for current condition monitoring in smart grids due to their high sensitivity, low power consumption, and compact size. However, designing ME sensors that simultaneously achieve low magnetic noise and a large linear range remains challenging. In this work, we propose and systematically study a multilayered magnetoelectric sensor (MLMS). We experimentally demonstrate that the voltage noise is effectively suppressed by connecting the piezoelectric elements of the MLMS in series. Additionally, the magnetic flux concentration effect is weakened by magnetic shielding from the outer Metglas laminates, which increases the optimized bias field to 52 Oe for the MLMS. Consequently, an equivalent magnetic noise as low as 16.7 pT/rtHz at 1 Hz is obtained and an enlarged linear range from 20 pT to 2 mT is achieved. Furthermore, we demonstrate that the proposed MLMS could linearly detect a wide range of power currents from 0.1 mA to 400 A, with nonlinear error and current resolution as low as 0.05% and 0.1 mA, respectively. [ABSTRACT FROM AUTHOR]

Parabolic monocapillary X-ray lens (PMXRL) is an ideal optical device for constraining the point divergent X-ray beams to quasi-parallel beams, but the overlap of direct X-rays and reflected X-rays through PMXRL deteriorates the outgoing beam divergence. Aiming to solve this problem, this study designs and tests a square-shaped lead occluder (SSLO) embedded in PMXRL to block the direct X-rays passing through the PMXRL. Python simulations are employed to determine the geometric parameters of the SSLO as well as the optimal position of the SSLO in the PMXRL according to our proposed model. The PMXRL with a conic parameter p of 0.000939 mm and a length L of 60.8 mm is manufactured and the SSLO with a size of 0.472 mm×0.472 mm×3.4 mm is embedded into it. An optical path system based on this PMXRL is built to measure the divergence of the outgoing X-ray beam. The experimental results show that the quasi-parallel X-ray beam reaches a divergence of 0.36 mrad in the range from 15–45 mm at the PMXRL outlet. This divergence is 10 times lower than the theoretical divergence without SSLO. Our work provides an alternative method for obtaining highly parallel X-ray beam and is beneficial to generate or facilitate new applications of monocapillary optics in X-ray technology. [ABSTRACT FROM AUTHOR]

Magnetoelectric (ME) sensors have enormous potential for detecting weak magnetic fields because of their high sensitivity, low power consumption, compact size and, low cost. However, inevitable vibration interference limits their application in practical environments, especially in the case of mobile platform mounting. Here, we propose a differential ME sensor, consisting of PZT macro-fiber composites (MFCs) and Metglas laminates. The differential ME sensor has two output terminals with weak mutual mechanical coupling and works in longitudinal vibration mode. MFC cores are polarized in parallel mode to guarantee their consistency of electric characteristics and reversed bias field is provided by attached magnets. Experimental results show that the differential-mode response amplitudes have a gain of −17.6 dB for low-frequency vibration at 2 Hz and ∼6.2 dB for an applied magnetic field at 3 Hz, in comparison with the single-ended mode. In addition, our proposed ME sensor also has a low inherent equivalent magnetic noise of 18.3 pT/√Hz at 1 Hz. Finally, a target detection experiment in the presence of heavy lab noise and strong vibration interference is conducted and the improved detection performance of the proposed differential ME sensor is proved. [ABSTRACT FROM AUTHOR]