Electromotive Force in Electrochemical Modification of Mudstone

This paper presented a novel analytical method for calculating magnetic field in the slotted air gap of spoke-type permanent-magnet machines using conformal mapping. Firstly, flux density without slots and complex relative air-gap permeance of slotted air gap are derived from conformal transformation separately. Secondly, they are combined in order to obtain normalized flux density taking account into the slots effect. The finite element (FE) results confirmed the validity of the analytical method for predicting magnetic field and back electromotive force (BEMF) in the slotted air gap of spoke-type permanent-magnet machines. In comparison with FE result, the analytical solution yields higher peak value of cogging torque.

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EVANOHM ALLOY S

Alloy Digest ◽

10.31399/asm.ad.ni0373 ◽

1989 ◽

Vol 38 (7) ◽

Keyword(s):

Electrical Resistivity ◽

Corrosion Resistance ◽

Physical Properties ◽

Tensile Properties ◽

Temperature Coefficient ◽

Electromotive Force ◽

Temperature Coefficient Of Resistance ◽

Resistance Wire ◽

High Electrical Resistivity ◽

Optimum Stability

Abstract EVANOHM alloy S offers optimum stability and flexibility with regard to both size and required temperature coefficient of resistance. Its extremely low electromotive force vs copper together with its high electrical resistivity are highly desirable properties in a precision resistance wire. This datasheet provides information on composition, physical properties, and tensile properties. It also includes information on corrosion resistance as well as joining. Filing Code: Ni-373. Producer or source: Wilbur B. Driver Company.

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Research on the Non-Magnetic Conductor of a PMSM Based on the Principle of Variable Exciting Magnetic Reluctance

Energies ◽

10.3390/en14020318 ◽

2021 ◽

Vol 14 (2) ◽

pp. 318

Author(s):

Chunyan Li ◽

Fei Guo ◽

Baoquan Kou ◽

Tao Meng

Keyword(s):

Permanent Magnet ◽

Electromagnetic Force ◽

Electromotive Force ◽

Permanent Magnets ◽

Permanent Magnet Synchronous Motor ◽

Synchronous Motor ◽

Magnetic Conductor ◽

Critical Speeds ◽

Motor Structure ◽

Test Result

A permanent magnet synchronous motor (PMSM) based on the principle of variable exciting magnetic reluctance (VMRPMSM) is presented. The motor is equipped with symmetrical non-magnetic conductors on both sides of the tangential magnetized permanent magnets (PMs). By placing the non-magnetic conductor (NMC), the magnetic reluctance in the exciting circuit is adjusted, and the flux weakening (FW) of the motor is realized. Hence, the NMC is studied comprehensively. On the basis of introducing the motor structure, the FW principle of this PMSM is described. The shape of the NMC is determined by analyzing and calculating the electromagnetic force (EF) acting on the PMs. We calculate the magnetic reluctance of the NMC and research on the effects of the NMC on electromagnetic force, d-axis and q-axis inductance and FW performance. The critical speeds from the test of the no-load back electromotive force (EMF) verify the correctness of the NMC design. The analysis is corresponding to the test result which lays the foundation of design for this kind of new PMSM.

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The Equilibrium Phase Formation and Thermodynamic Properties of Functional Tellurides in the Ag–Fe–Ge–Te System

Energies ◽

10.3390/en14051314 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1314

Author(s):

Mykola Moroz ◽

Fiseha Tesfaye ◽

Pavlo Demchenko ◽

Myroslava Prokhorenko ◽

Nataliya Yarema ◽

...

Keyword(s):

Electromotive Force ◽

Equilibrium Phase ◽

Stoichiometric Composition ◽

Negative Electrode ◽

Electrochemical Cells ◽

Thermodynamic Quantities ◽

Positive Electrodes ◽

Gibbs Energies ◽

Buffer Region ◽

First Time

Equilibrium phase formations below 600 K in the parts Ag2Te–FeTe2–F1.12Te–Ag2Te and Ag8GeTe6–GeTe–FeTe2–AgFeTe2–Ag8GeTe6 of the Fe–Ag–Ge–Te system were established by the electromotive force (EMF) method. The positions of 3- and 4-phase regions relative to the composition of silver were applied to express the potential reactions involving the AgFeTe2, Ag2FeTe2, and Ag2FeGeTe4 compounds. The equilibrium synthesis of the set of phases was performed inside positive electrodes (PE) of the electrochemical cells: (−)Graphite ‖LE‖ Fast Ag+ conducting solid-electrolyte ‖R[Ag+]‖PE‖ Graphite(+), where LE is the left (negative) electrode, and R[Ag+] is the buffer region for the diffusion of Ag+ ions into the PE. From the observed results, thermodynamic quantities of AgFeTe2, Ag2FeTe2, and Ag2FeGeTe4 were experimentally determined for the first time. The reliability of the division of the Ag2Te–FeTe2–F1.12Te–Ag2Te and Ag8GeTe6–GeTe–FeTe2–AgFeTe2–Ag8GeTe6 phase regions was confirmed by the calculated thermodynamic quantities of AgFeTe2, Ag2FeTe2, and Ag2FeGeTe4 in equilibrium with phases in the adjacent phase regions. Particularly, the calculated Gibbs energies of Ag2FeGeTe4 in two different adjacent 4-phase regions are consistent, which also indicates that it has stoichiometric composition.

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Electromotive force induced by the moving non-magnetic phase in ferrofluids

Sensors and Actuators A Physical ◽

10.1016/j.sna.2020.112472 ◽

2021 ◽

Vol 317 ◽

pp. 112472

Author(s):

Feng Jiao ◽

Qian Li ◽

Yongqing He

Keyword(s):

Electromotive Force ◽

Magnetic Phase

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STANDARD ELECTROMOTIVE FORCE OF THE CELL H2; HBr(m), AgBr; Ag FROM 0 TO 50°

The Journal of Physical Chemistry ◽

10.1021/j100814a012 ◽

1962 ◽

Vol 66 (8) ◽

pp. 1423-1426 ◽

Cited By ~ 47

Author(s):

Hannah B. Hetzer ◽

R. A. Robinson ◽

Roger G. Bates

Keyword(s):

Electromotive Force

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Development of Three-Phase Permanent-Magnet Synchronous Motor Drive with Strategy to Suppress Harmonic Current

Energies ◽

10.3390/en14061583 ◽

2021 ◽

Vol 14 (6) ◽

pp. 1583

Author(s):

Wei-Tse Kao ◽

Jonq-Chin Hwang ◽

Jia-En Liu

Keyword(s):

Permanent Magnet ◽

Electromotive Force ◽

Permanent Magnet Synchronous Motor ◽

Synchronous Motor ◽

Motor Drive ◽

Actual Measurement ◽

Current Harmonic ◽

Three Phase ◽

Measurement Results ◽

Harmonic Components

This study aimed to develop a three-phase permanent-magnet synchronous motor drive system with improvement in current harmonics. Considering the harmonic components in the induced electromotive force of a permanent-magnet synchronous motor, the offline response of the induced electromotive force (EMF) was measured for fast Fourier analysis, the main harmonic components were obtained, and the voltage required to reduce the current harmonic components in the corresponding direct (d-axis) and quadrature (q-axis) axes was calculated. In the closed-loop control of the direct axis and quadrature axis current in the rotor reference frame, the compensation amount of the induced EMF with harmonic components was added. Compared with the online adjustment of current harmonic injection, this simplifies the control strategy. The drive system used a 32-bit digital signal processor (DSP) TMS320F28069 as the control core, the control strategies were implemented in software, and a resolver with a resolver-to-digital converter (RDC) was used for the feedback of angular position and speed. The actual measurement results of the current harmonic improvement control show that the total harmonic distortion of the three-phase current was reduced from 5.30% to 2.31%, and the electromagnetic torque ripple was reduced from 15.28% to 5.98%. The actual measurement results verify the feasibility of this method.

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