Search results for "power system"
showing 10 items of 322 documents
Quantifying residential PV feed-in power in low voltage grids based on satellite-derived irradiance data with application to power flow calculations
2016
AbstractA scheme using satellite-derived irradiance measurements to model the feed-in power of residential photovoltaic (PV) systems in a low voltage distribution grid is described. It is validated against smart meter measurements from a test site with 12 residential PV systems in the city of Ulm, Germany, during May 2013 to December 2014. The PV feed-in power is simulated in a 15-min time resolution based on irradiance data derived from Meteosat Second Generation satellite images by the physically based retrieval scheme Heliosat-4. The PV simulation is based on the nominal power and location of the PV systems as provided by the distribution system operator. Orientation angles are taken fro…
Feasibility analysis and study of a grid-connected hybrid electric system: Application in the building sector
2016
This paper represents the feasibility study and analysis of a grid-connected hybrid (PV-Wind) system with battery, realized within the project DE.DU.ENER.T and installed in the research centre CRTEn located in the northern Tunisia in the city of Borj-Cedria. The main objective of this work is to exploit renewable sources of electrical energy production to electrify the desired building. So, to minimize electricity consumption costs, reduce the adverse effects of pollutants products from the diesel power systems and sometimes happen to sell the surplus of energy produced. The HOMER (Hybrid Optimization Model of Electric Renewable) software is used to estimate system size and its performance …
A New Method for the Price Determination of the Reactive Power Supply
2006
This paper addresses the development of an accurate model for the pricing of reactive power supply as an ancillary service. Reactive power supply is one of the most important ancillary services in the field of transmission systems security. The present work is focused on building a reactive power market at which the Distributors can also take part in injecting reactive power at the connected HV/MV nodes. The authors have studied the particular case of the reactive power supplied by sub-transmission or distribution networks, connected to the nodes of the transmission system. The aim of this work is to establish a reactive power price by crossing demand and offer curves.
Review of photovoltaic status in a European (EU) perspective
2011
In the EU continent, a generation cost around 0.15€/kWh has been achieved [1]. Around the world, there is a mission to stimulate this green source of energy and it is believed that by 2030, PV will be able to deliver around 9 % of the world's electricity demands. According to an International Energy Agency (IEA) report [2], it is expected that PV will accomplish grid parity in at least 10% of the world by 2020. There was a significant 60 % annual growth in the grid connected PV systems in the span of 2004–2009 [3]. The present article will bring out the status & review of PV technology and the details of PV system standards as suggested by IEA. In the present paper, the main attention has b…
A methodology for optimisation of solar dish-Stirling systems size, based on the local frequency distribution of direct normal irradiance
2021
Abstract In geographical areas where direct solar irradiation levels are relatively high, concentrated solar energy systems are one of the most promising green energy technologies. Dish-Stirling systems are those that achieve the highest levels of solar-to-electric conversion efficiency, and yet they are still among the least common commercially available technologies. This paper focuses on a strategy aimed at promoting greater diffusion of dish-Stirling systems, which involves optimizing the size of the collector aperture area based on the hourly frequency distributions of beam irradiance and defining a new incentive scheme with a feed-in tariff that is variable with the installed costs of…
Voltage Security Assessment by Using PFDT and CBR Methods in Emerging Power System
2018
Abstract This paper exhibits varied methods for voltage security assessment in a restructured power system. This paper primarily lays emphasis on two methods that are Probabilistic Fuzzy Decision Tree (PFDT) and Case Based Reasoning (CBR). In PFDT, Decision Tree plays an integral role for classification of system. For further classification of power system security, an algorithm is developed to categorise the buses which trouble the security most. After classification of system, by using minimum amount of load curtailment of voltages on buses which made insecure to secure load. Optimization of load is done by curtailing reactive power from insecure buses. In CBR, old cases from database are…
An original control strategy of storage systems for the frequency stability of autonomous grids with renewable power generation
2021
This work examines the operation of the autonomous power system of a geographical island assuming the integration of significant generation shares from renewable energy sources and the installation of the required storage systems. The frequency stability of the system is investigated considering different operating conditions, in terms of load demand and renewable power generation. The main focus of the work is an original control strategy specifically designed for power converters interfacing storage units to the grid. The proposed strategy is based on an extended frequency droop control, which selects specific droop settings depending on the operating mode—charge or discharge—of the stora…
Quantifying the Potential Economic Benefits of Flexible Industrial Demand in the European Power System
2018
The envisaged decarbonization of the European power system introduces complex techno-economic challenges to its operation and development. Demand flexibility can significantly contribute in addressing these challenges and enable a cost-effective transition to the low-carbon future. Although extensive previous work has analyzed the impacts of residential and commercial demand flexibility, the respective potential of the industrial sector has not yet been thoroughly investigated despite its large size. This paper presents a novel, whole-system modeling framework to comprehensively quantify the potential economic benefits of flexible industrial demand (FID) for the European power system. This …
A self-synchronizing instrument for harmonic sources detection in power systems
2004
The deregulation of energy markets holds out new prospects for contract between customers and utilities, in which the price of energy can depend on voltage quality and load characteristics, as well as on the responsibility for disturbances caused to supply voltage in power systems. In this context, harmonic sources detection is one of the main problems, because of equipment sensibility and the proliferation of loads which absorb non-sinusoidal currents. In this paper the authors present a new instrument based on a time domain method for the detection of harmonic active powers in three-phase systems, which can be usefully applied even in the presence of unbalance or asymmetry. The amplitude …
Metrological characterization and operating principle identification of static meters for reactive energy: an experimental approach under nonsinusoid…
2009
In this paper, an experimental approach is proposed for the metrological characterization of the static meters for reactive energy and for the individuation of their operating principle in nonsinusoidal conditions. The proposed approach was developed by starting from the only available accuracy test condition in the presence of the harmonics introduced by the standards for active static meters. In this paper, the proposed approach is described, and some experimental tests are presented, which were performed on some meters of different accuracy classes and with both known and unknown operating principles.