Results 261 to 270 of about 33,988 (309)

A study on randomly varying harmonic currents and total harmonic distortion of currents in power systems

2005 International Conference on Future Power Systems, 2005
Harmonic analysis is an important application to power systems and an efficient approach to evaluate the injected total harmonic distortion (THD) of currents flowing into a power system due to the summation of randomly varying harmonic currents produced by AC-to-DC power converters is presented in this paper.
null Li Wang, null Kuo-Hua Liu
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Current harmonics in nonlinear resistance circuits

Electrical Engineering, 1935
A semigraphical method of solving for harmonics in the input current to a network containing any number of linear and nonlinear resistances in any combination, when a sinusoidal voltage is applied across the network, is presented herewith. The treatment is restricted to nonlinear resistances in which the d-c volt-ampere characteristic is the same ...
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Transformer inrush - Harmonics in the current

2018 19th International Scientific Conference on Electric Power Engineering (EPE), 2018
When transformer is energized, a transient current up to 10 to 15 times larger than the rated transformer current can flow for several cycles. The differential protections are mainly sensitive during this time, as the inrush current flows just on one site of the transformer and so it creates false differential current.
Bermann Jiri, Prochazka Martin
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Voltage and current harmonics caused by corona

Journal of the American Institute of Electrical Engineers, 1921
THE FOLLOWING investigation was made to study the effects of corona in producing voltage and current harmonics in transmission systems. In the early work on corona in 1910 a very complete oscillographic study was made of voltage and current. It was found that the current wave of corona loss very much resembled the excitation current wave of a ...
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Reducing Supply Current Harmonics

IEEE Industry Applications Magazine, 1998
In this article, a simple and effective method for reducing the supply current harmonics has been proposed for a parallel connected 12-pulse thyristor converter with an interphase reactor. The proposed method requires only an interphase reactor with an optimal inductance value being much smaller than conventional inductance values, without any ...
Toshihiko Tanaka, Naotsugu Koshio, Hirofumi Akagi, Akira Nabae   +3 more
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Divisors and Harmonic Currents

2001
In the first two sections of the present chapter we introduce a conjecture (Conjecture 7.1) which specifies the idea that the characterization of the divisor of the Selberg zeta function of the a-twisted geodesic flow proved in Chapter 3 Section 3.3 is related to its characterizations in terms of a-twisted harmonic currents on SX.
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Harmonic reduction in thyristor converters by harmonic current injection

IEEE Transactions on Power Apparatus and Systems, 1976
The paper describes analytical and experimental results for a new method of current harmonic reduction in thyristor converters. The principle of the method is to modify the current waveforms on the d.c. windings of the converter transformer by injecting harmonic currents at a particular frequency.
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Even harmonics in alternating-current circuits

Proceedings of the American Institute of Electrical Engineers, 1909
In the usual presentation and consideration of wave-forms in alternating-current circuits we are so used to the mathematical expressions which omit the second, fourth, sixth, etc. harmonics and so generally assume that these even harmonics can be neglected at the outset, that a short consideration of usual and special conditions, giving rise to even ...
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Superposition of current and voltage harmonics

2018 ELEKTRO, 2018
This paper deals with power quality that is aimed on voltage and current harmonics. The analysis describes the household appliances producing the harmonic interference, because they consist of semiconductor components. The next reason is that a large number of household appliances are operated in the same time.
Andrej Bolf, Alena Otcenasova, Michal Regula, Marek Novak   +3 more
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Non-Harmonic Alternating Currents

Transactions of the American Institute of Electrical Engineers, 1927
Certain principles are presented for solving non-harmonic a-c. problems. Graphical methods are already well known for solving practically any problem, when currents and electromotive forces are sinusoidal, by vector diagrams in a plane. In certain special cases such diagrams give correct results when currents and electromotive forces are non-sinusoidal,
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