High-frequency transformation of Rhizobium meliloti [PDF]
Journal of Bacteriology, 1988 Transformation of R factor RP4 and its derivative pRK290 from Escherichia coli to Rhizobium meliloti is reported. The efficiency of transformation was in the range of 10(-5) per viable cell. In addition, chromosomal DNA prepared from one R. meliloti strain resistant to streptomycin was transferred to the isoleucine-valine-requiring mutant susceptible ...
J, Courtois, B, Courtois, J, Guillaume
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Development of a Medium Voltage, High Power, High Frequency Four-Port Solid State Transformer
CES Transactions on Electrical Machines and Systems, 2022 The power and voltage levels of renewable energy resources is growing with the evolution of the power electronics and switching module technologies.
Ahmad El Shafei +4 more
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A new behavioural model for performance evaluation of common mode chokes [PDF]
, 2007 A galvanically isolated three-phase AC/AC converter with a high-frequency AC-link has been analyzed from an EMC point of view. This is a special configuration because of a large number of switches, a high frequency transformer, and a fourwire output. The
Bergsma, H. +5 more
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Mine inverter based on isolation and transformation of power electronic transformer
Gong-kuang zidonghua, 2021 At present, the mine inverter and the power frequency transformer are placed separately, which occupies too much underground working space. And the inverter output voltage has high harmonic content and poor waveform quality.
ZHANG Guilin1,2 +4 more
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Power Transformer Condition Monitoring Based on Evaluating Oil Properties
Machines, 2022 The authors review the techniques applied to diagnose oil aging. Further, the authors put forward a new diagnostic method. It stipulates for an additional high-frequency measuring loop formed in an operating transformer.
Ivan V. Bryakin +4 more
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High frequency transformer computer modeling [PDF]
2007 Australasian Universities Power Engineering Conference, 2007 Frequency response analysis (FRA) technique is nowadays widely used in both factory and field applications as a diagnostic tool for power transformers. The main problem about FRA techniques is to interpret the observed evolution of the frequency response in order to identify failures.
Ahmed A. Siada, Syed Islam
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A New 7 kW Air-Core Transformer at 1.5 MHz for Embedded Isolated DC/DC Application
Energies, 2022 This paper presents the study of air-core transformers for electric vehicles, developing them for medium-power (tens of kWs) converter applications specifically used at a high frequency.
Valentin Rigot +3 more
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A novel energy router based on multi‐winding line frequency transformer
IET Generation, Transmission & Distribution, 2023 Energy routers based on the electronic power transformer are suitable for the AC–DC hybrid grid with multiple voltage levels, but their structures are complex.
Zhitao Guan +4 more
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Design optimization of a high-power transformer for three-phase dual active bridge DC-DC converter for MVDC grids [PDF]
, 2016 High-power DC-DC converter will be one of the essential technologies for the future DC grids. Especially, a three-phase dual-active bridge DC-DC (3DAB) Converter is highly suitable for high-power DC systems.
Feldman, Ralph +4 more
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Proposal of Three-Phase High Frequency Transformer Isolation UPS Topologies
Eletrônica de Potência, 2011 A family of double conversion three-phase uninterruptible power system with power factor correction and high-frequency transformer (HFT) isolation topologies is presented in this work.
Carlos G. C. Branco +3 more
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