Results 301 to 310 of about 1,917,176 (346)

Very fast phase angle estimation algorithm for a single-phase system having sudden phase angle jumps

Conference Record of the 2002 IEEE Industry Applications Conference. 37th IAS Annual Meeting (Cat. No.02CH37344), 2003
This work proposes a very fast phase angle estimation algorithm for a single-phase system under a sudden phase angle jump condition. When a source voltage changes in a step manner, the normal phase angle detector, such as a phase locked loop (PLL) and a (low pass) filter, typically generates phase delay and results in a sluggish response, and causes ...
null Hong-Seok Song, null Kwanghee Nam, P. Mutschler   +2 more
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A phase angle standard

Measurement Science and Technology, 2004
A phase angle standard for power frequencies (40–400 Hz) with a very low measuring uncertainty of 3 µrad is developed. The standard is based on a two-channel high-stability arbitrary waveform AC source for voltages up to 120 V and currents up to 6 A with high phase angle resolution which is realized as a development device with full computer control. A
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Phase angle regulating transformer protection

IEEE Transactions on Power Delivery, 1994
This paper describes the protection of a 345 kV, 450 MVA three phase, phase angle regulating (PAR) transformer. The transformer includes load tap changers which permit phase angle variations of 25/spl deg/ advance to 25/spl deg/ retard in a total of 32 steps (16 advance, 16 retard).
M.A. Ibrahim, F.P. Stacom
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Ratiometer phase angle indicator

Journal of Scientific Instruments, 1960
The principle of the moving coil ratiometer is described together with the circuit used with it for phase angle measurement. The mode of operation, performance, adjustment, and calibration are given.
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Ultralinear small-angle phase modulator

Proceedings of the 45th Annual Symposium on Frequency Control 1991, 2002
A DC electric field applied to a quartz plate resonator causes changes in the elastic constants which can lead to a change in the frequency of the resonator. This effect, known as the polarizing effect, has been shown to be extremely linear. A method for measuring the polarizing effect in high-Q SC-cut 5-MHz quartz resonators for small AC electric ...
J. Lowe, F.L. Walls
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Progress in phase angle thermography

Review of Scientific Instruments, 2003
Phase angle thermography is basically spatially multiplexed photothermal radiometry. It provides images for remote detection and imaging of damage. For energy deposition one can use external heat sources (e.g., light or convective heating) or internal heat generation (e.g., electric current, microwaves, eddy current, or elastic wave).
A. Dillenz, T. Zweschper, G. Riegert, G. Busse   +3 more
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The Phase Angle of Current Transformers

Transactions of the American Institute of Electrical Engineers, 1915
A method of testing the phase angle of current transformers by comparing readings obtained on a wattmeter whose current circuit is first connected to receive a part of the primary current (the remainder of the primary current passing in shunt through resistance) and then connected to the secondary circuit; the potential circuit is supplied from the ...
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The Diagnostic Value of Phase-Angle Tympanograms

International Journal of Audiology, 1981
The diagnostic value of susceptance, conductance, resistance, reactance, admittance and phase-angle tympanograms is compared. Phase-angle tympanograms seem to be best suited for the discrimination between normal W patterns and broad irregular curves obtained from ossicular disruptions, luxations and necroses.
W L, Creten, K J, Van Camp, M A, Maes, P M, Vanpeperstraete   +3 more
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Remote measurement of phase angle

Proceedings of the Institution of Electrical Engineers, 1972
A system is described for the measurement of the phase angle between two voltages separated from each other, and from the point where the results are to be displayed, by a distance of several miles. A correction for the transmission delay of the measurement signals is automatically made, and an accurate knowledge of the transmission-path ...
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Improved-accuracy phase angle measurement

International Journal of Electronics, 1976
A method for phase angle determination from measurement of three magnitudes, described in a recent paper (Middlebrook 1975), is extended to provide improved accuracy.
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