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Techniques for the realization of ultrareliable spaceborne computers Interim scientific report [PDF]

Error-free ultrareliable spaceborne ...
Goldberg, J., Green, M. W., Levitt, K. N., Stone, H. S.   +3 more
core   +1 more source

Construction of bosonic string theory on infinitely curved Anti-de Sitter space

, 2003
Free scalar field theory in the sector with a large number of particles can be interpreted as bosonic string theory on anti-de Sitter space of vanishing radius.
Adam Clark, Andreas Karch, Daisuke Yamada, G. ’t Hooft, H. J. De Vega, I. R. Klebanov, O. Aharony, Pavel Kovtun, R. Giles, R. Kallosh, R. R. Metsaev, S. Dalley, S. J. Chang, T. Banks   +13 more
core   +1 more source

Study on the Influence of Inconsistent Valve Parameters on LCC-HVDC Commutation and Operation

IEEE Access, 2019
Line commutated converter high voltage direct current (LCC-HVDC) transmission has unique advantages and plays an irreplaceable role in the power system. It is of great significance to study the commutation process.
Yanyong Yang, Pinjia Zhang
doaj   +1 more source

A Suppression Method of Commutation Failure in LCC-UHVDC Systems Based on the Dynamic Tracking of the Turn-Off Angle Setting Value

Electronics
Commutation failure is still one of the most common faults in LCC-UHVDC (line commutated converter-based, ultra-high voltage direct current) systems, and if the inverter side, extinction angle, and rectification value remain constant during the fault, it
Hua Wang, Ao Zheng, Ziwen Liu, W. Liu, Xueqing Pan, Chunsun Tian   +5 more
semanticscholar   +1 more source

Rapid identification method of commutation failure risk areas in HC-HVDC systems under single-phase faults

International Journal of Electrical Power & Energy Systems
The hybrid cascaded high voltage direct current (HC-HVDC) systems combine MMC and LCC features. However, single-phase ground faults on the AC lines of the receiving end power grid can easily cause LCC commutation failure on the inverter side.
He Wang, Sunao Liu, Jing Bian, Guoqing Li, Jiazhi Guo, Yuming Fu   +5 more
doaj   +1 more source

Quantum optical effective-medium theory for layered metamaterials

, 2016
The quantum optics of metamaterials starts with the question whether the same effective-medium theories apply as in classical optics. In general the answer is negative.
Amooghorban, Ehsan, Wubs, Martijn
core  

Coordinated Control for Operating Characteristics Improvement of UHVDC Transmission Systems under Hierarchical Connection Scheme with STATCOM

Energies, 2019
Ultra-high voltage direct current (UHVDC) systems under hierarchical connection schemes (HCSs) linked to AC grids with different voltage levels (500 and 1000 kV) have been a great concern for power utilities to transfer bulk power.
Atiq Ur Rehman, Chunyi Guo, Chengyong Zhao   +2 more
doaj   +1 more source

Analysis of successive commutation failure influence on power angle stability of large power grid

Journal of Physics: Conference Series
Successive commutation failure seriously threatens the safe operation of large AC/DC power grids, which may lead to cascading failures across regional power grids.
Ming Wang, Yuanzhen Zhu, Zhaohao Jia, Yiheng Chen, Runjia Sun   +4 more
semanticscholar   +1 more source

Adaptive VDCOL control strategy for the recovery of the UHVDC SPC system

The Journal of Engineering, 2019
The separating pole connection (SPC) mode of ultra-high-voltage direct current (UHVDC) can significantly improve the power stability, but when the AC bus of one pole is failed and two receiving systems are near, it may cause subsequent commutation ...
Shujun Yao, Wenerda Huang, Wenbo Hao, Guo Wanhua   +3 more
doaj   +1 more source

Detecting Topological Order with Ribbon Operators

, 2016
We introduce a numerical method for identifying topological order in two-dimensional models based on one-dimensional bulk operators. The idea is to identify approximate symmetries supported on thin strips through the bulk that behave as string operators ...
Bridgeman, Jacob C., Flammia, Steven T., Poulin, David   +2 more
core   +1 more source