Results 41 to 50 of about 2,792 (271)

Loss reduction analysis and control of AC-voltage-boosted FBSM MMC by injecting second harmonic circulating current

The Journal of Engineering, 2019
Reducing the power loss and handling short-circuit faults in HVDC systems are crucial for economical and reliable operation of modular multilevel converters (MMC). This paper proposes a loss reduction method for AC voltage-boosted FBSM-MMC by controlling
Muchao Xiang, Jiabing Hu, Zhiyuan He
doaj   +1 more source

A VSM (virtual synchronous machine) convertor control model suitable for RMS studies for resolving system operator/owner challenges [PDF]

, 2016
In recent years, it has become clear that reaching the targeted levels of renewable power generation poses problems, not only for basic infrastructure and generation/load balancing, but also in terms of fundamental network stability.
Booth, Campbell, Dyśko, Adam, Ierna, Richard, Roscoe, Andrew J, Urdal, Helge, Yu, Mengran, Zhu, Jiebei   +6 more
core  

The (Glg)ABCs of cyanobacteria: modelling of glycogen synthesis and functional divergence of glycogen synthases in Synechocystis sp. PCC 6803

FEBS Letters, EarlyView.
We reconstituted Synechocystis glycogen synthesis in vitro from purified enzymes and showed that two GlgA isoenzymes produce glycogen with different architectures: GlgA1 yields denser, highly branched glycogen, whereas GlgA2 synthesizes longer, less‐branched chains.
Kenric Lee, Dimitrios Bekiari, Sofia Doello, Karl Forchhammer   +3 more
wiley   +1 more source

Improved design of passive damping for single phase grid‐connected LCL filtered inverter considering impedance stability

IET Power Electronics
Grid‐connected inverters with an inductor–capacitor–inductor (LCL) filter usually require the implementation of damping in the filter to suppress the resonance associated with the filter and hence ensure internal stability.
Ramy Ali, Hamed Heydari‐doostabad, Shahab Sajedi, Terence O'Donnell   +3 more
doaj   +1 more source

Study on overvoltage of hybrid LCC-VSC-HVDC transmission

The Journal of Engineering, 2018
Hybrid line commutation converter-voltage-source converter high-voltage direct current transmission (LCC-VSC-HVDC) power transmission has unique technical advantages, but its overvoltage study is not sufficient at present.
Dizhen Xu, Xiaobin Zhao, Yuxin Lu, Kang Qin, Long Guo   +4 more
doaj   +1 more source

Gut microbiome and aging—A dynamic interplay of microbes, metabolites, and the immune system

FEBS Letters, EarlyView.
Age‐dependent shifts in microbial communities engender shifts in microbial metabolite profiles. These in turn drive shifts in barrier surface permeability of the gut and brain and induce immune activation. When paired with preexisting age‐related chronic inflammation this increases the risk of neuroinflammation and neurodegenerative diseases.
Aaron Mehl, Eran Blacher
wiley   +1 more source

A novel and easy‐to‐implement modulation scheme for reducing modulation complexity in modular multilevel converter

IET Power Electronics
Modulation strategy plays a key role in the operation of modular multilevel converters (MMC). Although many studies have been carried out on its optimization in MMC, the limitations of hardware implementation are seldom considered.
Zichen Wang, Zhijie Liu, Ke‐Jun Li, Jinxin Dou, Zhonglin Guo, Xiaoxue Ge   +5 more
doaj   +1 more source

Singular value decomposition-based dynamic response analysis of VSC-MTDC/AC systems for renewable energy integration

The Journal of Engineering, 2019
The dynamic performance of voltage source converter-based multi-terminal high-voltage direct current (VSC-MTDC) grid for large-scale renewable energy integration is becoming a concern.
Hua Ye, Yao Liu, Yanan Tang, Wei Pei, Li Kong   +4 more
doaj   +1 more source

A methionine‐lined active site governs carbocation stabilization and product specificity in a bacterial terpene synthase

FEBS Letters, EarlyView.
This study reveals a unique active site enriched in methionine residues and demonstrates that these residues play a critical role by stabilizing carbocation intermediates through novel sulfur–cation interactions. Structure‐guided mutagenesis further revealed variants with significantly altered product profiles, enhancing pseudopterosin formation. These
Marion Ringel, Carl P. O. Helmer, Shani Zev, Ronja Driller, Emily Buhr, Markus Reinbold, Renana Schwartz, Gabriel Foley, Mikael Boden, Daniel Garbe, Gerhard Schenk, Dan Thomas Major, Bernhard Loll, Thomas Brück   +13 more
wiley   +1 more source

Analysis and improvement of the reactive power cascade control strategy for MMC‐HVDC receiving‐end converter connected to weak grid

IET Generation, Transmission & Distribution
The weak AC grid in a modular multilevel converter modular multilevel converter based high voltage direct current (MMC‐HVDC) receiving‐end system requires faster reactive power support from the receiving‐end MMC.
Junhua Xu, Guopeng He, Yong Liu, Songqin Tang, Daiyu Xie, Mingyuan Chen   +5 more
doaj   +1 more source