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Measurements of Planetary Electric Currents
Nature, 1964Theories of an electric current generated by the earth's magnetic field are presented. Preliminary measurements d of the current were undertaken, using telephone cables in the Pacific Ocean near Australia. Voltage at the ends of the cables, one end being earthed'' under the ocean, was measured.
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Current Density Measurements in Atmospheric Electricity
Nature, 1967IN 1929, Watson1 pointed out that very close to the surface of the Earth the atmospheric electric current, in normal fine weather field, is carried only by positive ions, so that the current density can be computed from where J is the density of the current from ionosphere to Earth, Es is the electric field at the surface, and λ+s is the conductivity ...
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Evaluating measurement uncertainty in electric current measurement in PQ determination
Eurocon 2013, 2013The determination of power quality levels, through objective approach, is based on recordings of measurement information. For a more complete characterization of power quality parameters, the measurement process is required to include measurements of the alternating current as well, as specified in IEC 61000-4 series regulations "Electromagnetic ...
Niculai Stanciu +2 more
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A Motor Current Signal-Based Bearing Fault Diagnosis Using Deep Learning and Information Fusion
IEEE Transactions on Instrumentation and Measurement, 2020Bearing fault diagnosis has extensively exploited vibration signals (VSs) because of their rich information about bearing health conditions. However, this approach is expensive because the measurement of VSs requires external accelerometers. Moreover, in
Duy-Tang Hoang, Hee-Jun Kang
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Measuring Electrical Current: The Roads Not Taken
The Physics Teacher, 2011Recently I wrote about the standard Weston meter movement1,2 that is at the heart of all modern analogue current measurements. Now I will discuss other techniques used to measure electric current that, despite being based on valid physical principles, are largely lost in technological history.
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Electrical measurements on soil with alternating currents
Institution of Electrical Engineers - Proceedings of the Wireless Section of the Institution, 1934The electrical properties of the earth play an important part in many modern applications of physics and electrical engineering. In the early portion of this paper a summary is given of the published information on the electrical properties of soil for alternating currents at frequencies from 50 to nearly 200 million cycles per sec. Particular interest
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IEEE Sensors Journal, 2019
Traditional infrastructure and instrumentation methods in power system are transforming to cater the needs of modern and smart grid applications. In this process, contactless broad range electric current measurement has emerged as a hot research field ...
Yafeng Chen, Qi Huang, A. H. Khawaja
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Traditional infrastructure and instrumentation methods in power system are transforming to cater the needs of modern and smart grid applications. In this process, contactless broad range electric current measurement has emerged as a hot research field ...
Yafeng Chen, Qi Huang, A. H. Khawaja
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Current Measurement Gain Tuning Using High Frequency Signal Injection
2007 IEEE Industry Applications Annual Meeting, 2007Accurate measurement of the phase currents in electric machines is a requirement for most high performance drives. Incorrect current measurement gain estimates, caused by device tolerances, temperature drifts, age and noise, reduce the accuracy of the ...
M. Harke +4 more
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The Measurement of Electric Current and Voltage
2018Textbooks on mechanics usually begin with the concepts of length, time, and mass. The measurement apparatus which has been tried and tested in everyday life is described, i.e. rulers, clocks and balances, and they are immediately put to use. No one uses a sundial or a water clock for the first experiments, or even a slave who is beating time.
Klaus Lüders, Robert Otto Pohl
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Novel Noncontact Eddy Current Measurement of Electrical Conductivity
IEEE Sensors Journal, 2018A new noncontact method for measuring the electrical conductivity of metals based on eddy current testing is proposed for the physics that the logarithm of phase signals of impedance change is linear to that of electrical conductivity. A finite element model for simulations was built, and the mathematical relationship between the logarithm of phase ...
Cuiping Wang +4 more
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