Results 301 to 310 of about 1,874,316 (354)

High-frequency investigation of planar transformers

2014 International Conference on Electrical Sciences and Technologies in Maghreb (CISTEM), 2014
Planar 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, Hamed Belloumi, Tarek Ben Salah, Ferid Kourda   +3 more
openaire   +1 more source

Transformer model for high frequencies

IEEE Transactions on Power Delivery, 1988
A 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.
openaire   +1 more source

High frequency wideband power transformer design

[Proceedings] 1992 IEEE International Conference on Systems, Man, and Cybernetics, 2003
The 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, M.A. Morill, V.A. Caliskan, C.Q. Lee   +3 more
openaire   +1 more source

High-Frequency Planar Transformer Parameter Estimation

IEEE Transactions on Magnetics, 2015
This 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, Daming Zhang, John E. Fletcher   +2 more
openaire   +1 more source

High–Frequency Transformation of Penicillium Chrysogenum

Nature Biotechnology, 1987
We 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, B. Díez, J. L. Barredo, E. Alvarez, J. F. Martín   +4 more
openaire   +1 more source

Optimization Design of High-Power High-Frequency Transformer Based on Multi-Objective Genetic Algorithm

IEEE Power Engineering and Automation Conference, 2018
With the increase of the transformer capacity and converter switching frequency, the transformer efficiency, stray parameters, insulation and heat dissipation should be considered when designing a transformer.
Ke Zhang, Wu Chen, Xiaopeng Cao, Zhanfei Song, Guangyao Qiao, Li Sun   +5 more
semanticscholar   +1 more source

A new type high frequency transformer

IEEE Transactions on Magnetics, 1991
In order to realize small power supplies, the authors propose a type of coreless high-frequency transformer. This transformer is composed of simple twisted coils and its operating principle is based on the skin effect of current carrying conductors. Approximate analysis based on the symmetrical current distributions in each of the coil axes has been ...
S. Hayano, Y. Nakajima, H. Saotome, Y. Saito   +3 more
openaire   +1 more source

Modeling of high-frequency micro-transformers

IEEE Transactions on Magnetics, 2004
A dynamic model has been developed to predict the efficiency of a micro-transformer, operating at 5 MHz. The model includes a core hysteresis model, core eddy current model and winding copper loss model. Measurements and finite element analysis were carried out in order to validate the model.
null Ningning Wang, H. Hauser, T. O'Donnell, M. Brunet, P. McCloskey, S.C. O'Mathuna   +5 more
openaire   +1 more source

High-Frequency Impedance Transformations

2010
Active devices such as transistors or Op-Amps have bandwidth limitations that can result in instability or undesirable dynamic response in feedback circuits. As gain decreases with frequency, feedback-amplifier port-resistance values also change and effectively become reactive. These bandwidth-related reactances can resonate with other circuit elements.
openaire   +1 more source

A Study on High Frequency Transformer Design in Medium-voltage Solid-state Transformers

2018 Asian Conference on Energy, Power and Transportation Electrification (ACEPT), 2018
High switching frequency (HF) operation of solid-state transformers (SSTs) reduces the weight and volume of magnetic parts. Yet in medium-voltage (MV) SSTs, electrical insulation becomes a great concern and demands extra spacing.
Chih-Shen Yeh, J. Lai
semanticscholar   +1 more source