Spelling suggestions: "subject:"uninterruptible power aupply"" "subject:"uninterruptible power asupply""
1 |
Fuel cells as a backup energy source for high availability network serversHumphrey, Daniel Alan 10 October 2008 (has links)
This thesis proposes an uninterruptible power supply, UPS for high availability
servers with fuel cells as its back up energy source. The system comprises a DC to DC
converter designed to accommodate the fuel cellâ s wide output voltage range. A server
power supply is specified, designed and simulated for use with this UPS. The UPS
interfaces internal to the server power supply, instead of providing standard AC power.
This topology affords enhanced protection from faults and increases overall efficiency of
the system by removing power conversions. The UPS is simulated with the designed
power supply to demonstrate its effectiveness.
|
2 |
Redundans vid manöver med hjälp av UPSpå elnätetHöglund, Jonatan January 2016 (has links)
No description available.
|
3 |
Modelo de leilão multiperíodo para sistemas hidrotérmicos em mercados pool de energia do dia seguinte /Oliveira, Alberto Quialheiro January 2016 (has links)
Orientador: Leonardo Nepomuceno / Banca: Marcelo Augusto Cicogna / Banca: Edlaine Martins Soler / Resumo: Neste trabalho propõe-se um modelo de leilão multiperíodo para um mercado pool do dia seguinte de sistemas hidrotérmicos, que leve em consideração as restrições intertemporais do sistema termelétrico (e.g. potência máxima disponível e limites de rampa e período mínimo de operação e desligamento) e restrições hidráulicas (e.g. defluência, volume e balanço de água, altura de queda, alturas de montante e jusante do reservatório, limites de rampa de vazão defluente e função de produção). Também foram introduzidas no modelo as restrições de rede de transmissão, tais como o balanço e limites de fluxo de potência e representação das perdas. São descritas as técnicas de linearização das funções de altura de queda líquida, função de produção e função de perdas no sistema de transmissão. O modelo proposto é formulado como um problema de programação linear inteiro-misto, tendo sido resolvido utilizando as plataformas GAMS - CPLEX e IBM ILOG CPLEX Optimization Studio. Os resultados apresentados têm como foco principal a análise do impacto das restrições hidráulicas nos preços de equilíbrio de mercado e no despacho de geração de sistemas hidrotérmicos. Mostra-se que a operação de uma cascata hidráulica para o dia seguinte é orientada com base nas ofertas fornecidas pelas companhias geradoras no mercado de energia. / Abstract: This work presents a brief description of an energy market structure, as well as its agents, economic division and service and time horizon classification. The Brazilian mar-ket, single-period and multiperiod auction are also described, as much as a concise presen-tation of a hydroelectric generation system. It's proposed for a day-ahead pool market, a multiperiod auction for hydrothermal system which takes into account the intertempo-ral constraints from a thermoelectric system (e.g. maximum available power output and ramp rate limits, minimum up and down time) and hydraulic constraints (e.g. defluence, volume and water balance, net head, forebay and tailrace levels of reservoir, water release ramp rate limits and the unit performance curves). It was also associated to the problem the transmission constraints, such as balance and flow power limits and power loss. On account of being a problem with such features, the linearization techniques of the net head, unit performance curves and power loss function are described. The proposed mo-del is based on a mixed integer linear programming problem, which used the GAMS -CPLEX and IBM ILOG CPLEX Optimization Studio to its resolution. Finally there are two reported situations to analyze the impact of the hydraulic constrains on the bidding prices, as well as the in˛uence of the selling prices on the total spillage of the hydroelectric plants. The model is projected for a hydro predominance plant cascade. / Mestre
|
4 |
Voltage-source inverter output waveform compensation using adaptive intelligent control /Barnes, Lemuel Gregory, January 1994 (has links)
Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1994. / Vita. Abstract. Includes bibliographical references (leaves 388-392). Also available via the Internet.
|
5 |
Digital control of pulse width modulated inverters for high performance uninterruptible power suppliesMarwali, Mohammad Nanda Rahmana, January 2004 (has links)
Thesis (Ph. D.)--Ohio State University, 2004. / Title from first page of PDF file. Document formatted into pages; contains xviii, 224 p.; also includes graphics. Includes bibliographical references (p. 199-211).
|
6 |
A universal controller for a single-phase uninterruptible power supply system /Cheng, Limin, January 1998 (has links)
Thesis (M. Eng.), Memorial University of Newfoundland, 1999. / Bibliography: p. 113-115.
|
7 |
Composite converters with cascaded high frequency and pulsed linksDe Rooij, Michael Andrew. 20 August 2012 (has links)
D.Ing. / In this dissertation a pulsed DC voltage bus comprising a full wave rectified sinusoidal voltage will be investigated for use as a link voltage. A background study into existing converter topologies for single phase uninterruptable power supplies and three phase front end converters, applicable to the study, is discussed. The definition of the bus voltage will be given as well as the power handling limitations. An experimental 3.3kW single phase UPS and a 3.3kW three phase front end converter using the bus was designed, built, tested and the results presented. The design and modelling of the two systems are discussed so as to clarify the advantages, disadvantages and limits of using such a bus. The appropriate standards pertaining the two converter systems have been looked up and the impact on the design discussed. The discussion will be concluded with a summarisation and possible future work is discussed.
|
8 |
A new UPS topology and deadbeat control techniques for improved utility interface compatibilityKamran, Farrukh 12 1900 (has links)
No description available.
|
9 |
PIC kontrollü kesintisiz güç kaynağı tasarımı ve gerçekleştirilmesi /Bayram, Yasemin. Çalış, Hakan. January 2007 (has links) (PDF)
Tez (Yüksek Lisans) - Süleyman Demirel Üniversitesi, Fen Bilimleri Enstitüsü, Elektronik Bilgisayar Eğitimi Anabilim Dalı, 2007. / Bibliyografya var.
|
10 |
Dynamic digital control schemes for three-phase UPS invertersUys, Jacobus Johannes 12 1900 (has links)
Thesis (MScEng)--University of Stellenbosch, 2002. / ENGLISH ABSTRACT: This thesis presents the design and implementation of a voltage controller for an
Uninterruptible Power Supply (UPS) Inverter. The inverter is capable of producing a
nearly sinusoidal output voltage waveform, thereby keeping the Total Harmonic
Distortion (THD) to a minimum.
Digital controllers introduce a time delay in the control law that causes system
instability. Various control techniques, which includes Pade approximations and
system augmentation, are investigated to eliminate the effect of the time delay. These
controllers employ classical control as well as modem control techniques. The
selection of the various control parameters is verified by mathematical equations. A
load-disturbance compensation scheme, implementing feed-forward and gain
scheduling, is also developed to improve voltage distortion when varying loads, such
as non-linear loads, are connected to the system. It is shown that the constructed
pulse-width modulated (PWM) control scheme can achieve fast dynamic response as
well as a low THD. / AFRIKAANSE OPSOMMING: Hierdie verhandeling ondersoek die ontwerp en implementering van 'n spanningsbeheerder
vir 'n ononderbroke kragtoevoer omsetter. Die stelsel produseer 'n uittree
spannigsgolfvorm met 'n lae Totale Harmoniese Distorisie (THD).
Digital beheerders veroorsaak 'n tydvertraging in die beheerwet wat stelsel
onstabiliteit kan veroorsaak. Verskeie beheertegnieke wat gebaseer is op die Pade
benaderings van die tydvertraging en stelsel aanpassings, is ondersoek. Hierdie
beheerders maak gebruik van klassieke en moderne beheertegnieke. Die seleksie van
die verskeie beheerderveranderlikes word gestaaf deur wiskundige vergelykings.
Spannigsvervorming word tot 'n minimum beperk deur gebruik te maak van 'n
lasveranderings-kompensasietegniek wat onderskeidelik vorentoe-voer en aanwins
skedulering implementeer. Verder word daar bewys dat die pulswydte modulasie
(PWM) beheerskema vinnige dinamiese gedrag asook 'n lae THD bewerkstellig.
|
Page generated in 0.0773 seconds