Search Results: 1 - 10 of 100 matches for " "
All listed articles are free for downloading (OA Articles)
Page 1 /100
Display every page Item
Safety Impact of Large-Scale Distributed PV Power Access to Power Grids  [PDF]
Hualing Han,Ning Chen,Linan Qu,Tao Shi
International Journal of Computer and Electrical Engineering , 2013, DOI: 10.7763/ijcee.2013.v5.716
Abstract: Photovoltaic (PV) power generation is the fastest growing part of distributed generation technologies. Large-scale PV power connected to the grid is bound to the safe operation of the grid to bring new problems and challenges in China. Based on PSASP, combined with large-scale PV power access to the actual grid, this article establish PV model, do research on the characteristics of large-scale PV power stations and network system. In this article, the characteristics of PV grid-connected systems, stability and other issues accessing to large-scale PV system are discussed.
Experimental Study of the Cloud Influence on PV Grid Connected System  [PDF]
Yassir Idris Abdalla Osman, Jinping Li, Xiaofei Zhen, Airong Yang
Smart Grid and Renewable Energy (SGRE) , 2018, DOI: 10.4236/sgre.2018.91001
Abstract: In recent years, PV panels witnessed a vigorous gross, as their performance and the leverage of large-scale industrial production steadily decreased costs. Factors such as solar irradiance, insolation, mismatch of modules/arrays characteristic, aging, partial shading situation have a major effect on the harvested power. Evidence suggests that partial shading situation is the most critical factor and causes a significant reduction in PV system output. In this paper, a method based on two degrees of freedom, namely upper and lower was proposed in order to address the partial shading losses that due to cloud movement. Moreover, an extensive simulation of voltage, current indicators, bypassed modules, fault string, and DC output power was presented to analyze the PV system. The validation of experimental data analysis was carried out on two different days with different amounts of solar irradiance in Minqin County, Gansu Province, China. The results indicated that the power losses were 18.989 W and 127.629 W according to the minimum and the maximum irradiations (1.88 MW/m2) and (2.104 MW/m2) respectively. By considering the minimum irradiance, the upper and the lower degrees of freedom of the losses were 22.17 W/d, and 15.8 W/d respectively. On the other hand, by considering the maximum irradiance, the upper and the lower degrees of freedom were 130.49 W/d, 125.78 W/d respectively.
Large Scale In Silico Screening on Grid Infrastructures  [PDF]
N. Jacq,V. Breton,H. -Y. Chen,L. -Y. Ho,M. Hofmann,H. -C. Lee,Y. Legré,S. -C. Lin,A. Maass,E. Medernach,I. Merelli,L. Milanesi,G. Rastelli,M. Reichstadt,J. Salzemann,H. Schwichtenberg,M. Sridhar,V. Kasam,Y. -T. Wu,M. Zimmermann
Computer Science , 2006,
Abstract: Large-scale grid infrastructures for in silico drug discovery open opportunities of particular interest to neglected and emerging diseases. In 2005 and 2006, we have been able to deploy large scale in silico docking within the framework of the WISDOM initiative against Malaria and Avian Flu requiring about 105 years of CPU on the EGEE, Auvergrid and TWGrid infrastructures. These achievements demonstrated the relevance of large-scale grid infrastructures for the virtual screening by molecular docking. This also allowed evaluating the performances of the grid infrastructures and to identify specific issues raised by large-scale deployment.
Transient Analysis of Large Scale PV Systems with Floating DC Section  [PDF]
Morris Brenna,Alberto Dolara,Federica Foiadelli,George C. Lazaroiu,Sonia Leva
Energies , 2012, DOI: 10.3390/en5103736
Abstract: The increasing penetration of renewable sources with power-electronic interfaces in power systems is raising technical problems and the overall efficiency of photovoltaic systems can decrease dramatically. In this context, the optimal layout for the photovoltaic system is required. The most adequate strategy to connect the renewable system to the electrical power grid or to supply the end users must be adopted. The present paper proposes a design layout of a PV plant using a DC bus system to improve the overall energy conversion efficiency. An analysis of steady-state system stability, voltage drop and DC cable conduction losses is conducted. The leakage currents to the ground are investigated through simulations. Experimental results are shown focused on the analysis of optimal layout of photovoltaic systems under particular operating conditions.
Tapping the Potential of Large Scale Solar PV System in Sabah: The Feasibility Analysis  [PDF]
Maryam Huda, Keiichi Okajima, Kengo Suzuki
Energy and Power Engineering (EPE) , 2017, DOI: 10.4236/epe.2017.92009
Abstract: As a developing country with the rapid growth of economic and population like Malaysia, energy and electricity play a critical role towards sustaining and supporting the development of the nation. However, like many countries across the world, Malaysia is facing challenges in reducing the carbon footprint while attending the expanding growth. In the Eleventh Malaysia Plan, Malaysia has pledged to renew and increase its commitment to the environment and long-term sustainability by adopting green growth initiatives. According to the plan, one of the approaches towards pursuing green growth is by undertaking the sustainable consumption and production concept that promotes economic growth without compromising the environment. One of the strategies is to focus on promoting renewable energy sources as well as boosting up the development of the systems. The last decade has seen a growing trend towards renewable energy in Malaysia, particular in solar photovoltaic applications in recent years. This paper will investigate the potentials of installing 5 MW solar PV plants in the state of Sabah according to feed in tariff incentives and its financial and environmental assessment in order to promote large scale solar PV in Malaysia. This paper calculates the economic viability through IRR and simple payback indicators and the environmental impact through CO2 emission reduction indicator for the proposed 5 MW plant.
Partial Shading of PV System Simulation with Experimental Results  [PDF]
Basim A. Alsayid, Samer Y. Alsadi, Ja’far S. Jallad, Muhammad H. Dradi
Smart Grid and Renewable Energy (SGRE) , 2013, DOI: 10.4236/sgre.2013.46049

In a solar photovoltaic array, it is possible that shadow may fall over some of its cells. Under partial shading conditions the PV characteristic gets more complex with multiple peaks. The purpose of this paper is to illustrate, by analyzing different shading situations, the effects that partial shading can cause in a PV array. First this is done by simulation using Matlab/Simulink, then the impact of shading is illustrated experimentally by measurements on a two commercial 140 W PV panels series connected.

Scheme analysis on GW-scale coastal mud flat PV system connected to power grid

, CAO Zenggong, MU Hong, WANG Chunyi, LIU Yutian

- , 2017, DOI: 10.6040/j.issn.1672-3961.0.2016.492
Abstract: 摘要: 为了减小百万千瓦级滩涂光伏接入对电网的影响,保证电网的安全稳定经济运行,分析了百万千瓦级滩涂光伏电站接入电网的不同方案,提出将百万千瓦级光伏电站分为电气上相对独立又相互关联的两部分,分别就近接入两个变电站的220 kV侧,并给出了其接入电网的基本原则,既满足了大规模光伏接入的需要,又保障了电网的安全稳定运行。以山东电网为例,从潮流分布、静态安全和暂态稳定等方面验证了所提并网方案的可行性。
Abstract: In order to reduce the effect of connecting GW-scale coastal mud flat photovoltaic(PV)system to the power grid and to ensure the secure, stable as well as economical operation of the power grid, different connection schemes of connecting GW-scale coastal mud flat PV system to the power grid were analyzed. It was proposed that GW-scale coastal mud flat PV system was divided into two parts, which were electrically independent but correlative, and they were connected to the 220 kV sides of two nearby substations. The fundamental principle of connecting GW-scale PV system to the power grid was proposed. It not only satisfied the requirement of connecting large-scale PV system to the power grid, but also ensured the secure and stable operation of the power grid. The case study of Shandong power grid verified the feasibility of the proposed connection scheme in aspects of the load flow distribution, static security and transient stability
PV Systems Installed in Marine Vessels: Technologies and Specifications  [PDF]
Ioannis Kobougias,Emmanuel Tatakis,John Prousalidis
Advances in Power Electronics , 2013, DOI: 10.1155/2013/831560
Abstract: Considerations are held about the specificationin whichthe PV plants have to fulfill so that they can be installed on marine vessels. Initially, a brief description of the typical electrical grid of ships is presented, distinguishing the main parts, reporting the typical electrical magnitudes, and choosing the most preferable installation areas. The technical specifications,in whichthe PV plants have to be compatible with, are fully described. They are determined by the special marine environmental conditions, taking into consideration parameters like wind, humidity, shading, corrosion, and limited installation area. The work is carried out with the presentation of the most popular trends in the field of solar cell types and PV system technologies and their ability to keep up with the aforementioned specifications. 1. Introduction Without doubt the last decade was the golden age of the photovoltaic systems. The large number of technological breakthroughs on the research areas of power electronics, photovoltaic (PV) panels, and microgrids made the use of PV panels feasible to numerous applications of modern life. The PV systems of today generate electric power that ranges from W to MW. Small solar chargers for portable devices such as laptops, cell phones, and calculators are very popular. Single or arrays of PV panels produce electric power for street lights, advertising signs, isolated agricultural electric pumps, even small houses not connected to the utility grid. In addition, PV systems, wind power systems, batteries, fuel cell generators, and other renewable energy systems work together and organize reliable microgrids [1–4]. But the most common PV applications are the grid-tied ones, where single PV panels or large scale PV plants apply auxiliary electric power to the grid [4–7]. Despite their extended use at mainland applications, the PV systems presence in modern marine technology remains limited, mainly working as suppliers to small lighthouses, buoys, and chargers for the batteries of small sailing yachts [8, 9]. The rising transport expenses due to the fuel prices, the increasing restrictions of CO2 and nitric oxides emission due to new ecological policies, and generally the need for more eco-friendly transportation were the reasons that forced the marine companies to reexamine the systematic use of PV systems on large vessels [10–12]. The photovoltaic technology can indeed be a really cost-effective solution for ships. PV systems can act as ideal subsidiary power sources, independent from the vessel electromechanical settlement because they
Introducing Virtual Private Overlay Network Services in Large Scale Grid Infrastructures  [cached]
Francesco Palmieri
Journal of Computers , 2007, DOI: 10.4304/jcp.2.2.61-72
Abstract: The computational Grid concept is gaining great popularity as the best way to deliver access to a wide range of distributed computing and data resources. But, as Grids move from an experimental phase to real production and their deployment in the Internet significantly increases, controlling the security of a Grid application becomes imperative. The most significant Grid security issue is that the different sites composing the Grid will generally be managed by different organizations each with their own security mechanisms and policies. This makes any communication security arrangement on the entities participating to the Grid generally more difficult than if they were on the same LAN. In this paper, we propose a novel network resource abstraction for delivering dynamic on-demand Virtual Private Overlay connection services, into large-scale Grid environments. Such facility provides to Grid applications an illusion of dedicated layer-2 LAN connections that are fully comparable to a private network in performance, reliability, security and Quality of Service, but also provide topology and control plane virtualization to ensure better isolation also at the protocol and address space level. It may represent a technological breakthrough that can transform the overall connection paradigm in modern Grids, by reducing infrastructure costs, with the elimination of private circuits and long-distance direct connections, and increasing network coverage and flexibility by leveraging the Internet usage. As a proof of concept, the proposed facility has been implemented in a Grid Information Service prototype which was successfully tested on a small dedicated testbed infrastructure.
The Interaction between the Large-Scale EVs and the Power Grid  [PDF]
Yuan Huang, Junyong Liu, Xiaodong Shen, Tingting Dai
Smart Grid and Renewable Energy (SGRE) , 2013, DOI: 10.4236/sgre.2013.42017

With the problem of global energy shortage and peoples awareness of energy saving, electric vehicles receive world-wide attention from government to business. Then the load of the power grid will rapidly increase in a short term, and a series of effects will bring to the power grid operation, management, production and planning. With the large-scale penetration of electric vehicles and distributed energy gradually increased, if they can be effectively controlled and regulated, they can play the roles of load shifting, stabling intermittent renewable energy sources, providing emergency power supply and so on. Otherwise they may have a negative impact, which calls for a good interaction of electric vehicles and power grid. Analyzed the status of the current study on the interaction between the electric vehicles and the power grid, this paper builds the material basis, information architecture and the corresponding control method for the interaction from the aspect of the energy and information exchanging, and then discusses the key issues, which makes a useful exploration for the further research.

Page 1 /100
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.