STATCOM Helps to Guarantee a Stable System

B.R.Andersen,B.D.Gemmell,C.Horwill,D.J.Hanson 전력전자학회 2001 ICPE(ISPE)논문집 Vol.2001 No.10

Transmission System Operators are governed by operational security standards that are applied in real time. During system disturbances, the System Operators must rely on the installed protection and control equipment, prior to human intervention. New power electronic solutions bring rapid and repeatable responses to disturbances, which will help System Operators to guarantee a stable system. Last year, ALSTOM completed the world's first competitively bid STATCOM to Support the voltage on National Grid's 400kV network that supplies London and the Southeast from the north of the UK. ft is rated ±75MVAr and forms part of a Static Var System (SVS) with a total rating of 0 to 225MVAr. This paper will describe the reasons for its size, location, its chain-link configuration and give examples of its operating performance. The paper will also describe the features that allow this STATCOM to deliver much more than reactive compensation in support of a wider transmission service objective, as system conditions require.<br/> Index Terms-AC System, Chain Circuit Convertor, FACTS, GTO, STATCOM, SVC, Voltage-Sourced Convenors.

POWER TRANSMISSION BY HIGH VOLTAGE DIRECT CURRENT(HVDC)

B.R.Andersen 전력전자학회 2001 ICPE(ISPE)논문집 Vol.2001 No.10

Since the beginning of the last century, alternating current (ac) of 50 or 60Hz has been the dominant method for transmission and distribution of electric power. However, high voltage direct current transmission, normally called HVDC, can provide economic solutions for very long distances and enables interconnections between unsynchronised ac networks to be realised. World-wide HVDC schemes totalling 59GW with individual scheme ratings between 50MW and 6300MW have been installed and many more applications for this technology are being considered. This paper describes the characteristics of HVDC, the equipment involved, the uses of HVDC and outlines recent developments in the technology.<br/>

STATCOM Helps to Guarantee a Stable System

B.R.Andersen,B.D,Gemmell,C.Horwill,D.J Hanson 전력전자학회 2001 JOURNAL OF POWER ELECTRONICS Vol.1 No.2

Transmission System Operators are governed by operational security standards that are applied in real time. During system disturbances, the System Operators must rely on the installed protection and control equipment, prior to human intervention New power electronic solutions bring rapid and repeatable responses to disturbances, which will help System Operators to guarantee a stable system Last year, ALSTOM completed the world's first competitively bid STATCOM to support the voltage on National Grid's 400kV network that supplies London and the Southeast from the north of the UK. It is rated ±75MVAr and forms part of a Static Var System (SVS) with a total rating of 0 to 225MVAr. This paper will describe the reasons for its size, location, its chain-link configuration and give examples of its operating performance. The paper will also describe the features that allow this STATCOM to deliver much more than reactive compensation in support of a wider transmission service objective, as system conditions require.

STATCOM Helps to Guarantee a Stable System

Andersen, B.R,Gemmell, B.D.,Horwill, C.,Hanson, D.J. The Korean Institute of Power Electronics 2001 JOURNAL OF POWER ELECTRONICS Vol.1 No.2

Transmission System Operators are governed by operational security standards that are applied in real time. During system disturbances, the System Operators must rely on the installed protection and control equipment, prior to human intervention. New power electronic solutions bring rapid and repeatable responses to disturbances, which will help System Operators to guarantee a stable system. Last year, Alstom completed the world's first competitively bid STATCOM to support the voltage on National Grid's 400kV network that supplies London and the Southeast from the north of the UK. It is rated ${\pm}75MVAr$ and forms part of a Static Var System (SVS) with a total rating of 0 to 225MVAr. This paper will describe the reasons for its size, location, its chain-link configuration and give examples of its operating performance. The paper will also describe the features that allow this STATCOM to deliver much more than reactive compensation in support of a wider transmission service objective, as system conditions require.

Disulfide polymer grafted porous carbon composites for heavy metal removal from stormwater runoff

Ko, Dongah,Mines, Paul D.,Jakobsen, Mogens H.,Yavuz, Cafer T.,Hansen, Hans Chr. B.,Andersen, Henrik R. Elsevier 2018 Chemical engineering journal Vol.348 No.-

<P><B>Abstract</B></P> <P>The emerging concern of heavy metal pollution derived from stormwater runoff has triggered a demand for effective heavy metal sorbents. To be an effective sorbent, high affinity along with rapid sorption kinetics for environmental relevant concentrations of heavy metals is important. Herein, we have introduced a new composite suitable for trace metal concentration removal, which consists of cheap and common granular activated carbon covered with polymers containing soft bases, thiols, through acyl chlorination (DiS-AC). Material characterization demonstrated that the polymer was successfully grafted and grown onto the surface of the carbon substrate. The distribution coefficient for Cd<SUP>2+</SUP> bonding was 89·10<SUP>3</SUP> L/kg at a solution concentration of 0.35 mg/L, which is notably higher than sorption affinities for Cd<SUP>2+</SUP> seen in conventional sorbents. The sorption isotherm is well described by the Freundlich isotherm and within an hour, half of the initial trace (0.2 mg/L) concentration of Cd<SUP>2+</SUP> was removed by the DiS-AC at a sorbent loading of 2 g/L. Therefore, the novel material DiS-AC promises to be an ideal candidate for filters treating stormwater runoff.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The novel disulfide polymer grafted activated carbon composites were devised. </LI> <LI> Covalent bonds between disulfide polymer and carbon substrate have been proven. </LI> <LI> DiS-AC showed rapid kinetics on removing heavy metal in overall range of pH 6–8. </LI> <LI> DiS-AC showed high affinity towards even for trace amount of heavy metal in water. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Power Transmission by High Voltage Direct Current(HVDC)

Andersen, B.R. The Korean Institute of Power Electronics 2001 전력전자학회 논문지 Vol.6 No.4

지난 세기의 시작 아래로, 50Hz 또는 60Hz로 운영되는 교류는 저력 계통 망의 송전과 배전에 지배적으로 사용되는 방법이었다. 그러나, 일반적으로 HVDC라 불리는, 고압 직류 송전은 매우 긴 장거리 선로에 대한 경제적 해법을 제공하고 이미 실현 비 동기화 AC계통 사이의 연계를 가능케 하였다. 50MW에서 6300MW까지의 각 Scheme별로 건설된 직류송전은 전세계적으로 총 59GW HVDC Scheme이 설치되어있으며, 이 기술을 위해서는 더 많은 응용이 고려되고 있다. 본 원고에서는 HVDC의 특성, 포함된 설비, HVDC의 사용 그리고 기술 발전의 요약을 기술하였다.

First cosmology results using Type Ia supernova from the Dark Energy Survey: simulations to correct supernova distance biases

Kessler, R,Brout, D,D’Andrea, C B,Davis, T M,Hinton, S R,Kim, A G,Lasker, J,Lidman, C,Macaulay, E,Mö,ller, A,Sako, M,Scolnic, D,Smith, M,Sullivan, M,Zhang, B,Andersen, P,Asorey, J,Avelino, A,Calci Oxford University Press 2019 MONTHLY NOTICES- ROYAL ASTRONOMICAL SOCIETY Vol.485 No.1

Transcriptomic profiling reveals hepatic stem‐like gene signatures and interplay of miR‐200c and epithelial‐mesenchymal transition in intrahepatic cholangiocarcinoma

Oishi, Naoki,Kumar, Mia R.,Roessler, Stephanie,Ji, Junfang,Forgues, Marshonna,Budhu, Anuradha,Zhao, Xuelian,Andersen, Jesper B.,Ye, Qing‐,Hai,Jia, Hu‐,Liang,Qin, Lun‐,Xiu,Yamashita, Wiley Subscription Services, Inc., A Wiley Company 2012 Hepatology Vol.56 No.5

<P><B>Abstract</B></P><P>Intrahepatic cholangiocellular carcinoma (ICC) is the second most common type of primary liver cancer. However, its tumor heterogeneity and molecular characteristics are largely unknown. In this study, we conducted transcriptomic profiling of 23 ICC and combined hepatocellular cholangiocarcinoma tumor specimens from Asian patients using Affymetrix messenger RNA (mRNA) and NanoString microRNA microarrays to search for unique gene signatures linked to tumor subtypes and patient prognosis. We validated the signatures in an additional 68 ICC cases derived from Caucasian patients. We found that both mRNA and microRNA expression profiles could independently classify Asian ICC cases into two main subgroups, one of which shared gene expression signatures with previously identified hepatocellular carcinoma (HCC) with stem cell gene expression traits. ICC‐specific gene signatures could predict survival in Asian HCC cases and independently in Caucasian ICC cases. Integrative analyses of the ICC‐specific mRNA and microRNA expression profiles revealed that a common signaling pathway linking miR‐200c signaling to epithelial‐mesenchymal transition (EMT) was preferentially activated in ICC with stem cell gene expression traits. Inactivation of miR‐200c resulted in an induction of EMT, whereas activation of miR‐200c led to a reduction of EMT including a reduced cell migration and invasion in ICC cells. We also found that miR‐200c and neural cell adhesion molecule 1 (NCAM1) expression were negatively correlated and their expression levels were predictive of survival in ICC samples. NCAM1, a known hepatic stem/progenitor cell marker, was experimentally demonstrated to be a direct target of miR‐200c. Conclusion: Our results indicate that ICC and HCC share common stem‐like molecular characteristics and poor prognosis. We suggest that the specific components of EMT may be exploited as critical biomarkers and clinically relevant therapeutic targets for an aggressive form of stem cell‐like ICC. (H<SMALL>EPATOLOGY</SMALL> 2012;56:1792–1803)</P>

High-resolution Imaging of Transiting Extrasolar Planetary systems (HITEP) : II. Lucky Imaging results from 2015 and 2016

Evans, D. F.,Southworth, J.,Smalley, B.,Jørgensen, U. G.,Dominik, M.,Andersen, M. I.,Bozza, V.,Bramich, D. M.,Burgdorf, M. J.,Ciceri, S.,D’Ago, G.,Figuera Jaimes, R.,Gu, S.-H.,Hinse, T. C.,Henning, Th Springer-Verlag 2018 Astronomy and astrophysics Vol.610 No.-

<P><I>Context.</I> The formation and dynamical history of hot Jupiters is currently debated, with wide stellar binaries having been suggested as a potential formation pathway. Additionally, contaminating light from both binary companions and unassociated stars can significantly bias the results of planet characterisation studies, but can be corrected for if the properties of the contaminating star are known.</P><P><I>Aim.</I> We search for binary companions to known transiting exoplanet host stars, in order to determine the multiplicity properties of hot Jupiter host stars. We also search for and characterise unassociated stars along the line of sight, allowing photometric and spectroscopic observations of the planetary system to be corrected for contaminating light.</P><P><I>Methods.</I> We analyse lucky imaging observations of 97 Southern hemisphere exoplanet host stars, using the Two Colour Instrument on the Danish 1.54 m telescope. For each detected companion star, we determine flux ratios relative to the planet host star in two passbands, and measure the relative position of the companion. The probability of each companion being physically associated was determined using our two-colour photometry.</P><P><I>Results.</I> A catalogue of close companion stars is presented, including flux ratios, position measurements, and estimated companion star temperature. For companions that are potential binary companions, we review archival and catalogue data for further evidence. For WASP-77AB and WASP-85AB, we combine our data with historical measurements to determine the binary orbits, showing them to be moderately eccentric and inclined to the line of sight (and hence planetary orbital axis). Combining our survey with the similar Friends of Hot Jupiters survey, we conclude that known hot Jupiter host stars show a deficit of high mass stellar companions compared to the field star population; however, this may be a result of the biases in detection and target selection by ground-based surveys.</P>

Covalent organic polymer functionalization of activated carbon surfaces through acyl chloride for environmental clean-up

Mines, P.D.,Thirion, D.,Uthuppu, B.,Hwang, Y.,Jakobsen, M.H.,Andersen, H.R.,Yavuz, C.T. Elsevier 2017 Chemical engineering journal Vol.309 No.-

Nanoporous networks of covalent organic polymers (COPs) are successfully grafted on the surfaces of activated carbons, through a series of surface modification techniques, including acyl chloride formation by thionyl chloride. Hybrid composites of activated carbon functionalized with COPs exhibit a core-shell formation of COP material grafted to the outer layers of activated carbon. This general method brings features of both COPs and porous carbons together for target-specific environmental remediation applications, which was corroborated with successful adsorption tests for organic dyes and metals.