Results 81 to 90 of about 571 (264)

Parallel current-controlled synchronverters for voltage and frequency regulation in weak grids

The Journal of Engineering, 2019
The emulation of synchronous machines is becoming an attractive solution to provide virtual inertia and voltage support to weak grids and microgrids, representing an alternative to conventional current-injection control strategies.
Javier Roldán-Pérez, Alberto Rodríguez-Cabero, Milan Prodanovic   +2 more
doaj   +1 more source

C2α‐carbanion‐protonating glutamate discloses tradeoffs between substrate accommodation and reaction rate in actinobacterial 2‐hydroxyacyl‐CoA lyase

FEBS Open Bio, EarlyView.
Enzymes of the 2‐hydroxyacyl‐CoA lyase group catalyze the condensation of formyl‐CoA with aldehydes or ketones. Thus, by structural adaptation of active sites, practically any pharmaceutically and industrially important 2‐hydroxyacid could be biotechnologically synthesized. Combining crystal structure analysis, active site mutations and kinetic assays,
Michael Zahn, Barbara Seroka, Ryszard Lazny, Zenon Lotowski, Thore Rohwerder   +4 more
wiley   +1 more source

Weak Coupling Effects in the PLL Modes of Grid‐Following PMSG Wind Power Systems

IET Renewable Power Generation
Small‐signal synchronisation stability is a critical issue of grid‐connected permanent magnet synchronous generator (PMSG) wind power systems employing grid‐following voltage source converters (VSCs).
Xumeng Cui, Lei Chen, Kaiyuan Hou, Yong Min, Kefei Wang, Fei Xu   +5 more
doaj   +1 more source

High-voltage switch-mode assisted linear amplifier based voltage source for dielectric low frequency-domain spectroscopy measurements

The Journal of Engineering, 2019
This study presents a switch-mode assisted linear amplifier (SMALA) designed for use as a frequency-domain spectroscopy (FDS) excitation voltage source for the diagnostic testing of oil/paper insulation systems in large power transformers.
Shawn D. Nielsen, Geoffrey R. Walker, Geoffrey R. Walker   +2 more
doaj   +1 more source

Test Results From a Pair of 1-kWe Dual-Opposed Free-Piston Stirling Power Convertors Integrated With a Pumped NaK Loop

, 2011
As a step towards development of Stirling power conversion for potential use in Fission Surface Power (FSP) systems, a pair of commercially available 1-kW-class free-piston Stirling convertors were modified to operate with a NaK (sodium (Na) and ...
Geng, Steven M., Godfroy, Thomas J., Pearson, J. Boise, Briggs, Maxwell H., Penswick, L. Barry   +4 more
core  

Chameleon sequences reveal structural effects in proteins representing micelle‐like distribution of hydrophobicity

FEBS Open Bio, EarlyView.
Amino acids sequence of two different proteins with the same sequence (chameleon sequence—black boxes) represent in 3D structure of the proteins different secondary structures: HHHH—helical and BBB—Beta‐structural. The chains folded in water environment adopt different III‐order structures in which the chameleon fragments appear to adopt similar status
Irena Roterman, Katarzyna Stapor, Leszek Konieczny, Krzysztof Gądek, Piotr Nowakowski   +4 more
wiley   +1 more source

Corrected complex torque coefficient method for synchronization stability analysis of grid‐connected VSC

IET Renewable Power Generation
Sub‐synchronous oscillation of grid‐connected voltage source converter (VSC) dominated by phase locked loop (PLL) is an important stability issue in nowadays power systems.
Boyuan Zhao, Lei Chen, Yong Min, Yalou Li, Shiyun Xu   +4 more
doaj   +1 more source

Review of low voltage ride-through technology of doubly-fed induction generator

The Journal of Engineering, 2019
In recent years, with the increasing of wind power development, the demand for low voltage ride-through (LVRT) technology was proposed to ensure the safe and reliable operation of the power system.
Lele Niu, Xiao Wang, Linlin Wu, Feng Yan, Man Xu   +4 more
doaj   +1 more source

Design of Optimal QFT Controller and Prefilter for Buck Converter Using Metaheuristic Algorithms

, 2018
A buck converter is a step-down switching regulator. Buck convertors are being widely used in industrial applications that rely on regulated output voltage under fluctuating input voltage.
Nitish Katal, Shiv Narayan
core   +1 more source

Analysing the significance of small conformational changes and low occupancy states in serial crystallographic data

FEBS Open Bio, EarlyView.
This protocol paper outlines methods to establish the success of a time‐resolved serial crystallographic experiment, by means of statistical analysis of timepoint data in reciprocal space and models in real space. We show how to amplify the signal from excited states to visualise structural changes in successful experiments.
Jake Hill, Yelyzaveta Pulnova, Elke De Zitter, Helen M. Ginn, Briony A. Yorke   +4 more
wiley   +1 more source