Results 261 to 270 of about 148,673 (288)
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High frequency-selectivity impedance transformer
2015 IEEE Radio and Wireless Symposium (RWS), 2015This paper presents the design of an impedance transformer (IT) with high selectivity and wide out-of-band suppression characteristics. The proposed IT provides two transmission poles in the passband and a sharp frequency selective characteristic. For validation, a 50-to-20 Ω IT has been implemented at a center frequency (f 0 ) of 2.6 GHz.
Phirun Kim +4 more
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High-frequency planar power transformers
IEEE Transactions on Power Electronics, 1992High-frequency transformer design using the transmission line transformer (TLT) is described. Utilizing transmission line circuit theory, the characteristics of the TLT for different turn ratios are given, and its advantages, including its wideband nature, are discussed. TLT prototypes with turn ratios of 2:1, 3:1, and 5:1 were designed and fabricated.
M.A. Morrill, V.A. Caliskan, C.Q. Lee
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High frequency loss evaluation in high frequency multi-winding power transformers
Proceedings of 1995 IEEE Applied Power Electronics Conference and Exposition - APEC'95, 1995A high frequency power transformer (HFPT) with twin secondaries is generally analyzed with each primary ampere-turn being canceled by an equal contribution from each of the two secondaries. Such a methodology does not indicate worst case high frequency losses.
R.K. Dhawan, P. Davis, A.W. Lotfi
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High-frequency investigation of planar transformers
2014 International Conference on Electrical Sciences and Technologies in Maghreb (CISTEM), 2014Planar transformers are a novel type of devices used in integrated power systems. Having many advantages compared to classic wire wound technology; it's used to minimize size and weight and to increase their ability to withstand mechanical vibrations.
Aymen Ammouri +3 more
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High-Voltage, High-Frequency Transformer Design
2012Conversion of AC mains voltages to a high-voltage (>10 kV), high-power (>10 kW) DC level is a key area of technology which is a requirement in many industrial processes, for example, in particulate emission control using electrostatic precipitators. In the majority of cases, this high-voltage DC requirement is achieved with a singlephase AC regulator ...
Paul Lefley, Philip Devine
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High frequency models of PCB-based transformers
Proceedings of the 44th IEEE 2001 Midwest Symposium on Circuits and Systems. MWSCAS 2001 (Cat. No.01CH37257), 2002An equivalent network of PCB-based transformers with two windings is presented for use at high frequency (some MHz). After raising some criticisms to the traditional high frequency transformer model, a systematic procedure is presented to deduce the inductive and the capacitive coupling model of a two windings transformer.
ARTURI, CESARE MARIO +1 more
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High frequency wideband power transformer design
[Proceedings] 1992 IEEE International Conference on Systems, Man, and Cybernetics, 2003The transmission line transformer (TLT) is presented as a viable solution to the problem of high-frequency/wideband transformer design for the latest high frequency DC-DC resonant converters. Utilizing transmission line circuit theory, the authors present the characteristics of the TLT. Turn ratio 2:1 and 3:1 TLT prototypes with isolation were designed
D. Gan +3 more
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High-Frequency Planar Transformer Parameter Estimation
IEEE Transactions on Magnetics, 2015This paper presents different methods to determine the parameters for the equivalent electrical circuit model of a high-frequency planar transformer. The first method is implemented in the circuit simulation software utilizing a 1-D electromagnetic analysis.
Lew Andrew R. Tria +2 more
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High–Frequency Transformation of Penicillium Chrysogenum
Nature Biotechnology, 1987We report high–frequency transformation of penicillin–producing strains of Penicillium chrysogenum using plasmid vectors carrying the pyr4 gene of Neurospora crassa. Transformation to stable uracil independence is associated with acquisition of transforming DNA in high molecular forms that are not simple multimers of the vector.
J. M. Cantoral +4 more
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Transformer model for high frequencies
IEEE Transactions on Power Delivery, 1988A method for the development of a high-frequency transformer model for use in an electromagnetic transient program (EMTP) is discussed. A transformer to be modeled is measured, and the results are used to calculate the transfer and admittance functions. Modal analysis is used to determine a no-load network model that can be used in the EMTP.
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