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As one of the important parameters characterizing the cable's operation status, an accurate measurement of the current is particularly important for the cable's reliable operation and status monitoring. Aiming at the problem that the sum of the current phasors of multiphase cables is 0 when running in a steady state, and that the traditional mutual inductance current measurement method cannot be used for the phase current measurement of such cables, or that the insulation layer needs to be damaged, this paper proposes a non-contact measurement method of three-phase cable current, based on the magnetic field decoupling calculation. When combined with the actual parameters of the three-phase cable, the analytical calculation model of the magnetic field distribution of the three-phase cable is established. The relationship between the output ratio of the sensor and the deflection angle is obtained through theoretical derivation, the magnetic field coupling coefficient matrix is determined, and the transfer relationship between the output of the magnetic sensor and the current of each phase is clarified; an array magnetic field sensor is designed, which can sense the information of the adjacent magnetic field independently and is used for the reconstruction of three-phase currents. The effectiveness of the proposed method was tested on the built three-phase four-core cable current measurement test platform. The experimental results show that under the three-phase current balance, the measurement error of phase A, phase B and phase C is less than 2.8%, and the waveform and phase angle of the three-phase current can be well restored, which verifies the three-phase current measurement method proposed in this paper. [ABSTRACT FROM AUTHOR]

Utilizing temperature and magnetic field dependent dielectric spectroscopy, two different dielectric relaxation processes, both accompanied with prominent positive magnetodielectric (MD) effects, were observed in Pt/BiScO3-PbTiO3/La0.7Sr0.3MnO3 (Pt/BSPT/LSMO) heterostructure. An equivalent circuit model is established to quantitatively describe the relaxation data well. The simulation results elucidated that one relaxation process can be attributed to magnetic order associated BSPT/LSMO interfacial relaxation with abnormal dynamics feature. Another one is due to the external contact interface contributions. Both relaxation dynamics can be tuned, via magnetic field controlled localization of free interfacial charges, to induce MD effects in BSPT/LSMO interfaces and nonmagnetic Pt/BSPT contacts. [ABSTRACT FROM AUTHOR]

Dielectric relaxation and magnetodielectric (MD) effects were observed in 0.36BiScO3-0.64PbTiO3/La0.7Sr0.3MnO3 thin films. The universal dielectric response and distribution of relaxation time modifications were introduced into the Maxwell-Wagner (MW) model. Based on modified MW model, the negative MD response at low frequencies was attributed to magnetostriction of La0.7Sr0.3MnO3, while the large positive response at high frequencies mainly to the magnetoresistance of La0.7Sr0.3MnO3, and these two factors canceled each other out at intermediate frequencies. Moreover, a giant room temperature MD response of 9.5% was observed, and the linear MD response at 52 kHz was ascribed to the linear magnetoresistance effects. [ABSTRACT FROM AUTHOR]

Abstract: Polycrystalline La0.7Sr0.3MnO3 (LSMO) films were prepared on SiO2/Si (001) substrates by chemical solution deposition technique. Electrical and magnetic properties of LSMO were investigated. A minimum phenomenon in resistivity is found at the low temperature () under magnetic fields from 0 T to 3 T. Kondo-like spin dependent scattering, which includes both spin polarization and grain boundary tunneling, was observed in the low-temperature electrical transport for the LSMO polycrystalline films. The temperature-dependent resistivity at low temperatures can be well fitted in the framework of elastic scattering, electron–electron (e–e) interaction, Kondo-like spin dependent scattering, and electron–phonon (e–ph) interaction. [Copyright &y& Elsevier]

Pb0.7Sr0.3TiO3/La0.7Sr0.3MnO3 (PST/LSMO) thin film has been deposited on Si substrate by chemical solution deposition. Obvious changes in dielectric constant and loss as functions of frequency and magnetic field were observed in PST/LSMO thin film. By applying both dc bias electric and magnetic fields, apparent dielectric anomalies were observed in the 'butterfly-hysteresis' curves. These effects may be useful for practical application. The mechanism for the magnetocapacitance effects in PST/LSMO is rationalized by combining the Maxwell-Wagner capacitor model and the magnetoresistivity and magnetostriction of the LSMO. [ABSTRACT FROM AUTHOR]

Abstract: The magnetodielectric properties of BSPT/LSMO multiferroic composite thin films were investigated through the measurement of the frequency dependence of the dielectric constant under different magnetic fields at room temperature. The magnetodielectric (MD) response showed strong frequency dependence: at 100 Hz, the MD response remained negative and the maximum value of −1.1% was obtained; at 52 kHz, the dielectric constant first decreased and then rose linearly with the magnetic field until the giant room temperature positive MD effect of 9.5% was derived under 7 T. The observed unique MD effects for BSPT/LSMO were attributed to the co-contributions of the magnetostriction and magnetoresistance. [Copyright &y& Elsevier]