Operation Of Wind Power Plants Research Articles

Wind Power Forecasting in Short-Term Using Fuzzy K-Means Clustering and Bagging Neural Network

Wind power forecasting is the basic and essential task in the wind power plant operation. Wind power is one of the fast-growing feasible power resources and it will be viewed as the additional substitute for conservative power produced from the non-sustainable power source. The use of the conservative source of electricity will be reduced with the help of wind power forecasting (WPF). The fluctuation and instability of the wind will be difficult for collecting the original data and it will the major impact for forecasting the accuracy. Last few years many researchers use different data mining technique that has been applied in various prediction system that produced good forecasting accuracy. To improve the accuracy of the forecasting and reduce the computational complexity for a hybrid method is proposed that consist of fuzzy k-means clustering and Bagging Neural Network (BNN). In historical days there is a lot of similarities, fuzzy k-means clustering is used for clustering the similar days it consisting of the detailed information about historical data and weather conditions. In order to avoid the overfitting problem, a bagging algorithm to be incorporated with backpropagation neural network. For proving the efficiency, the proposed hybrid method will be evaluated in real wind farm which will provide better forecasting accuracy and also expected to reduce the computational complexity when compared with other existing wind power forecasting approaches.

Impact of different weather years on the design of hydrogen supply pathways for transport needs

Renewable energy sources (RES) will play a crucial role in future sustainable energy systems. In scenarios analyzing future energy system designs, a detailed spatial and temporal representation of renewable-based electricity generation is essential. For this, sufficiently representative weather data are required. Most analyses performed in this context use the historical data of either one specific reference year or an aggregation of multiple years. In contrast, this study analyzes the impact of different weather years based on historical weather data from 1980 through 2016 in accordance with the design of an exemplary future energy system. This exemplary energy system consists of on- and offshore wind energy for power-to-hydrogen via electrolysis, including hydrogen pipeline transport for most southwestern European countries. The assumed hydrogen demand for transportation needs represents a hypothetical future market penetration for fuel cell-electric vehicles of 75%. An optimization framework is used in order to evaluate the resulting system design with the objective function of minimizing the total annual cost (TAC) of the system. For each historical weather year, the applied optimization model determines the required capacities and operation of wind power plants, electrolyzers, storage technologies and hydrogen pipelines to meet the assumed future hydrogen demand in a highly spatially- and temporally-detailed manner, as well as the TAC of the system. Following that, the results of every individual year are compared in terms of installed capacities, overall electricity generation and connection to the transmission network, as well as the cost of these components within each region. The results reveal how sensitive the final design of the exemplary system is to the choice of the weather year. For example, the TAC of the system changes by up to 20% across two consecutive weather years. Furthermore, significant variation in the optimization results regarding installed capacities per region with respect to the choice of weather years can be observed.

CFD Analysis of Auditorium using Ansys Fluent

The documented investigation in this paper examines main power quality for wind turbines and its connection with the public grid. This main goal has been to investigate most popular type of wind turbines which are grid connected using doubly-fed induction generators (DFIG) at normal operation, as well as voltage control of these wind turbines after clearing a lines short circuit in the utility grid. This paper introduces the configuration of main portions of grid connected turbines, which have an importance in the wind power plants operation. It also proposes a new compact modeling of these wind turbines, which has a feature that the expressions of most plant portions are free of any complex or details that described in other past models. Most of last models are spotted on the normal operation of single wind turbines, without consideration of gird interaction faults. The proposed control techniques are new combined and concentrated on the voltage recovery, which plays very important role in the power quality and stability of wind turbines plants which are connected with the grid. Net simulation results show that the combination of pitch control and dynamic slip control could to have power system stability efficiently, and restore the voltage to its normal condition. A simulation of wind turbine using pitch control and dynamic slip control are developed by the simulation program is called power system computer aiding design (PSCAD) and carried out the stability investigations respecting to short circuit in external power lines system. After clearing of the fault, the recovery of voltage at the terminals of wind turbine should to rebuild, then the wind power turbine should going to its normal case. Control of the pitch angle or generator slip can adjusting the aerodynamic torque and the electromagnetic torque at the turbine which can be help to recovery the voltage at the terminals of wind turbine. The results of case study simulation are proved that pitch and dynamic slip controls ar

In-Service Wind Turbine DFIG Diagnosis Using Current Signature Analysis

Operation and maintenance costs of wind power plants represent a significant share of the total expenditure of a wind farm project. It is therefore vital to optimize maintenance activities in order to reduce costs while improving wind turbine reliability and availability. The induction generator is a major contributor to failure rates and downtime of wind turbines, where doubly fed induction generators (DFIGs) are the dominant variable-speed technology employed. Actual data from operating wind turbines is seldom presented in the scientific literature. This paper analyzes two in-service DFIGs from wind turbines operating in a Spanish wind power plant. One of the generators under study reported excessive temperature on the rotor windings, while the other did not. In order to achieve a diagnosis for the reported excess of temperature, current signature analyses were performed on both machines. Fault-related frequency components were identified in the current spectra of the faulty machine, and were compared against the healthy one. A diagnosis was achieved for the faulty machine: Dynamic eccentricity caused by a rotor fault was identified as the cause of the excessive temperature in the rotor windings.

THE TRENDS OF DRAWING UP THE ELECTRICITY BALANCE OF GEORGIA

The paper dwells on the analysis of electricity balance of Georgia in the years of 2005-2017 in accordance with the parameters such as electricity generation-consumption and exports-imports. Significant attention was paid to the structural development of electricity generation and consumption. The paper also addresses the issues of exports imports with neighboring countries. Electricity exports and imports in Georgia is characterized by changing dynamics. Over the past 17 years, imports have grown by 39,3%. It has been highlighted that the electricity balance in the years of 2016-2017 differs substantially from the electricity balance of previous years that is due to the operation of wind power plant, which just in 2017 generated 87,8 million kWh, representing 1% of generated electricity. The paper highlights that the level of electric intensity of production in Georgia is still high, the reduction of which is considerable room for improvement in the electricity balance; there is need for development of renewable energy resources (hydro, solar, wind), placing greater reliance on advanced technologies in the field of electricity consumption and so on.

ВЕТРОЭНЕРГЕТИЧЕСКИЕ РЕСУРСЫ ЦЕНТРАЛЬНЫХ РАЙОНОВ РЕСПУБЛИКИ АЛТАЙ

Актуальность исследования. Среди наиболее острых проблем, волнующих человечество, следует выделить энергетические проблемы. Они влияют непосредственно или опосредованно на человека, общество и окружающую среду. Человеческая деятельность связана с беспрерывным использованием природных энергоресурсов для обеспечения своей жизнедеятельности: теплом и светом в домах, продуктами питания, транспортом, одеждой и т. д. До настоящего времени во многих районах Сибири отсутствует централизованное энергоснабжение. Важной особенностью горных стран является большое рассредоточение потребителей электрической и тепловой энергии, неравномерная нагрузка в течение года и отсутствие централизованных источников энергии. Основным видом энергоисточников в горных районах являются дизельные электростанции. Стоимость получаемой энергии очень велика, особенно в отдалённых районах. Решение энергетической проблемы станет возможным лишь благодаря концепции освоения горных регионов с использованием возобновляемых источников энергии. В работе рассмотрены основные закономерности ветроэнергетического потенциала центральных районов Республики Алтай. Для выбора оптимального режима работы ветроэнергетических установок исходя из мощности электрических нагрузок, а также данных, необходимых для конструирования, расчётов, оценки прочности необходимы дополнительные исследования, в том числе микроклиматические наблюдения за ветровым режимом. Цель: оценить возможный вклад энергии ветра в энергоэффективность и улучшение экологических условий в горных районах Республики Алтай при интенсивном развитии туристско-рекреационной деятельности. Объекты: ветровой режим в нижней тропосфере над югом Сибири; орографические условия и их влияние на ветровой режим; ветроэнергетический потенциал среднегорных районов Республики Алтай. Методы: температурно-ветровое зондирование атмосферы; построение математической модели поля скорости ветра в нижней тропосфере на различных высотных уровнях; оценка и анализ влияния различных форм рельефа на скорость ветра. Результаты. Показано, что в условиях межгорных котловин и широких долин скорости ветра малы для развития ветроэнергетики. Анализ аэроклиматических показателей скорости ветра и данные высокогорных метеорологических станций на вершинах и водоразделах показали, что в условиях открытости горизонта ветроэнергетический потенциал достаточен для эффективной работы ветроэнергетических установок различной мощности. Для водораздельных участков выше 1500 м удельная мощность ветрового потока составляет от 150 до 850 Вт/м2, что позволяет эксплуатировать ветроэнергетические установки малой и средней мощности. За зону большой энергетики могут быть приняты районы с удельной мощностью ветрового потока более 500 Вт/м2. Такая зона может быть выделена в центральной части Горного Алтая, начиная примерно с 2200 м.

Integrated Energy Supply Schemes on Basis of Cogeneration Plants and Wind Power Plants

Abstract The paper presents innovative technological concepts of integrated energy supply schemes based on joint operation of thermal and wind power plants. The main advantage of these systems lies in the improving the efficiency, reliability and environmental friendliness of energy supply (electricity and heat). This is a result of fuel saving and reduction in CO2 emissions from thermal power plants, which becomes possible when part of fuel is replaced with electric power generated by wind turbines. The technological advantages of the proposed schemes are considered. These advantages expand the range of applications for the technologies both in small-scale and large-scale energy systems. A patent protects the proposed technologies.

Life Cycle Analysis of Ecological Impacts of an Offshore and a Land-Based Wind Power Plant

This study deals with the problems connected with the benefits and costs of an offshore wind power plant in terms of ecology. Development prospects of offshore and land-based wind energy production are described. Selected aspects involved in the design, construction, and operation of offshore wind power plant construction and operation are presented. The aim of this study was to analyze and compare the environmental impact of offshore and land-based wind power plants. Life cycle assessment analysis of 2-MW offshore and land wind power plants was made with the use of Eco-indicator 99 modeling. The results were compared in four areas of impact in order to obtain values of indexes for nonergonomic (impact on/by operator), nonfunctional (of/on the product), nonecological (on/by living objects), and nonsozological impacts (on/by manmade objects), reflecting the extent of threat to human health, the environment, and natural resources. The processes involved in extraction of fossil fuels were found to produce harmful emissions which in turn lead to respiratory system diseases being, thus, extremely dangerous for the natural environment. For all the studied areas, the impact on the environment was found to be higher for land-based wind power plants than for an offshore wind farm.

An analysis of wind and solar power variability to assess its implications for power grid

The paper discusses the problem of parallel operation of wind and solar power plants with the power system associated with the influence of power fluctuations on the power quality and stability. A brief assessment of the prospects for the commissioning of the wind and solar power plants in Russia and a description of the associated negative impacts on the power system is given. A methodology for assessing the possible energy production of wind and solar power plants using raw data from weather stations is presented. Based on the methodology, an assessment of some regions of Russia in relation to the variability of wind speed and cloudiness is made. The wind power duration curves are given. An analysis of possible deviations of solar power under the influence of cloudiness is carried out. The effect of geographical aggregation of wind or solar power output to increase the guaranteed power generation and reduce the negative impact on the stability of the energy system is shown.

Thermo-Ecological Cost of Electricity Generated in Wind Turbine Systems

Wind power is one of the most popular renewable energy sources (RES), characterized by rapid growth of installed power in the energy mix of many countries. Usually, the influence of wind technologies on the depletion of nonrenewable resources is evaluated taking into account the consumption of energy and materials in the construction phase. However, it should be noted that the major drawback of wind energy is its random availability which also influences the consumption of resources. This consumption results from the necessity of compensation for random operation of wind power plants by conventional ones operating in off-design point. In the present work, thermo-ecological cost (TEC) is proposed for the evaluation of the performance of wind generation systems operating with random accessibility of wind energy. The presented analysis focuses on the estimation of additional non-renewable energy consumption due to the part-load operation of the conventional power units. Different strategies are assumed for the compensation for the hourly wind power variations. The presented results of TEC analysis show that the part of TEC resulting from induced losses can be significant. The authors prove that, within the assessment of wind turbines, the induced losses cannot be omitted.

Consideration of reliability and economy to Capacity Configuration of energy storage system: Case Study of a large scale wind power plant in the Northwest China

Currently, a serious operation security problem of wind power plant has caused by the massive wind power integration, which has increased the difficulty of the operation in large scale wind power plant. Energy storage system (ESS) is thought the best choice to solve the operation scheduling problem of large-scale wind power plant, therefore, under the premise of ensuring the reliability of power supply and network constraints, it is particularly significant to select the proper capacity with both economy and feasibility, aiming at the problems above, this paper constructs capacity configuration of storage which is of statistical significance by studying the probability distribution characteristics, aiming at the deviation load during the operation of wind power plant, utilized Monte Carlo simulation, through whole lifetime NPV, payback period PBP and operation scheduling deviation OOD to verify the reliability and economy of the capacity. Finally, the actual operation data from a wind power plant installed 99MW in Northwest of China is utilized as a case study, simulation result shows that it could get the best storage capacity under the standard of the characteristics of economic and reliability criteria, which proves the validity and feasibility of the method in this paper.

Economic Effects of Wind Power Plant Deployment on the Croatian Economy

This paper tests the hypothesis that incentives for renewable energy sources contribute to economic development in Croatia. The aim of the paper is to quantify the total effects of wind power plant deployment on the Croatian economy in terms of employment and gross value. Indirect and induced effects are spread over the value added chain of producers of investment and intermediate goods and services required for wind power plant deployment and operation. The open input-output model is used for quantifying indirect effects. The closed input output model, which assumes endogenous personal consumption, is applied for quantifying total effects, which includes the effects of induced personal consumption. The gross value added and employment type I and type II multipliers related to wind power plants in Croatia were calculated separately for the investment and intermediate consumption channel. The results show positive indirect and induced effects relating to the deployment of wind power plants in Croatia. They are less pronounced in comparison to previous studies due to the undeveloped domestic production of equipment required for wind power plant deployment. Apart from the manufacturing sector, which produces equipment incorporated into wind power plants, the total effects were significant for construction, transport, and other supporting industries.

Calculation of wind speed in the 300-meter lower layer of the atmosphere based on the meteorological observations taking account of temperature stratification and surface roughness

Introduction. Taking into account relationship of wind profile power-law exponent (m) from hydrostatic stability of the layer and surface roughness the calculation method of wind speed and direction in the lower 300-meter layer of the atmosphere based on the meteorological observations is proposed.
 Problem. For many applied engineering problems, for example, for the design of high-rise construction and operation of wind power plants the wind and temperature profile data in the lower 300-meter layer are required. In the design, the main objective is to determine the peak wind loads and influences on objects.
 Research methods. The calculations were carried out using the energy-balance model of the atmospheric surface layer, SLEB, based on standard meteorological information. The model is built on the basis of Monin-Obukhov similarity. To determine spatial variability of wind and temperature hydrostatic stability of the atmosphere and the dynamic properties of the underlying surface are taken into account.
 Purpose. The aim of the study is to develop a method of calculation of changes in wind speed and direction in the lower 300-m layer of the atmosphere using the wind profile power law based on the standard surface meteorological information.
 Results of the study. Relationships of non-dimensional wind profile power-law exponent from hydrostatic stability of the layer and surface roughness, obtained with the SLEB model, allowed building function graphics for different observation times and months. All calculated values agree with the known experimental and theoretical data very well.

Research and application of a combined model based on variable weight for short term wind speed forecasting

Abstract Wind speed forecasting plays a prominent part in the operation of wind power plants and power systems. However, it is often difficult to obtain satisfactory prediction results because wind speed data comprise random nonlinear series. Current some statistical models are not proficient in predicting nonlinear time series, whereas artificial intelligence models often fall into local optima. For these reasons, a novel combined forecasting model, which combines hybrid models based on decomposed methods and optimization algorithms, is successfully developed with variable weighting combination theory for multi-step wind speed forecasting. In this model, three different hybrid models are proposed and to further improve the forecasting performance, a modified support vector regression is used to integrate all the results obtained by each hybrid model and obtain the final forecasting results. To verify the forecasting effectiveness of the proposed forecasting model, 10-min wind speed series from Penglai, China, are used as case studies. The experimental results indicate that the developed combined model not only outperforms other benchmark models but also can be satisfactorily used for planning for smart grids.

Impact of wind power plant operation on MV distribution grids

The study summarises the results of short-term voltage quality (VQ) measurements in medium-voltage distribution grids with connected wind power plants. The measurements were made in grids on supply territory of the utility E.ON Czech Republic in 2013–2016 period. VQ parameters were evaluated according to the standard EN 50160. Power flows of individual wind power plants were also evaluated and mutually were compared to find the pattern of their performance in various year seasons. Finally, an impact of wind power plant operation on VQ parameters, mainly on voltage variations and flicker, was analysed.

The effect of timescales on wind farm power variability with nonlinear model predictive control

AbstractModel predictive control techniques enable operators to balance multiple objectives in large wind farms, but the controller design depends on modeling effects that propagate at different timescales. This paper uses nonlinear model predictive control to investigate how wind farm power variability can be reduced both by varying ratios of three timescales impacting the system control and by inclusion of a power variability minimization measure in the controller objective function. Tests were conducted to assess how different timescale ratios affect the average farm power and power variability. Power variability measures are shown to be sensitive to the ratio of the incident wind period and the turbine time delay, particularly for cases with dominant incident wind frequencies. The average farm power increases in a series of steps as the controller time horizon increases, which corresponds to time horizon values required for wakes disturbances to propagate to downstream turbines. A second set of tests was conducted in which various measures of power variability were incorporated into the controller objective function and shown to yield significant reductions in farm power variability without significant reductions in farm power output. The controller was found to utilize two different approaches for achieving power variability reduction depending on the formulation of the controller objective function. These results have important implications for the design and operation of wind power plants, including the importance of considering the frequency components of wind during turbine siting and the potential to reduce power variability through the use of farm‐level coordinated control. Copyright © 2017 John Wiley & Sons, Ltd.

WIND POWER PLANT WITH THE SYSTEM OF SELECTIVE DISCONNECTION OF LOADS

The article represents a diagram of a wind power plant, at which there are the maximum use of the wind power and increase security of electricity supply to consumers. It substantiates the effectiveness of the scheme of autonomous wind power plant. Moreover, the article formulates conditions and the structure of the wind power plant operation scheme, and describes the principle of frequency control voltage generated by the wind power installation in a variety of situations and conditions. The use of selective disconnection of consumers makes it possible to increase the annual uninterrupted power supply of responsible consumers from 60% to 88%.

OBSERVAÇÕES E MODELAGEM DA CAMADA LIMITE INTERNA NO ENTORNO DE EXTENSOS SISTEMAS AQUÁTICOS

The determination of the spatial extent of the internal boundary layer (IBL) across a step change in surface roughness and surface heat flux and temperature is an important environmental aspect to the operation of industries, fossil-fuel, nuclear and wind power plants. The IBL of the land-water transition zone, such as in coastal regions, lakes and reservoirs, is strongly influenced by surface properties, as the roughness and stability change considerably within this zone. An observational study was conducted to measure meteorological properties near a large tropical reservoir and investigate the IBL at the water-land transition. A 42 m height meteorological mast was instrumented with sonic wind anemometers, air temperature and relative humidity sensors at 3, 10, 20 and 40 m height. Comparisons of the log profile model with the Monin-Obukhov similarity theory (MOS) and the observed wind profiles, shown that the MOS estimated the wind profile more accurately, especially if winds were from water to land.

Dynamic modelling and validation of pre-combustion CO2 absorption based on a pilot plant at the Buggenum IGCC power station

Based on the increasing concern about human-induced global warming, it is expected that constraints on carbon emissions will be much stricter in the future. Integrated gasification combined cycle (IGCC) power plants are an option in the attempt to mitigate the effect of CO2 emissions, because they can be fuelled or co-fuelled with biomass, but also, very importantly, because they can be equipped with pre-combustion CO2 capture units. Moreover, the rapidly growing share of electricity produced by converting renewable energy sources demands for more flexible operation of future IGCC plants in order to compensate for inherently intermittent operation of wind and solar power plants. The CO2 capture unit should therefore be able to follow the dynamic operation of the power plant, and, at the same time, meet environmental targets in terms of CO2 removal. In order to investigate and improve the transient performance of such complex systems, dynamic process simulations performed with accurate physically based models are essential. This paper presents the development and validation of the dynamic model of the absorption and solvent regeneration unit as part of a pre-combustion CO2 capture system, with focus on the absorber column model. The models are implemented into an open source software library following an object-oriented, equation-based modelling approach using the Modelica language. The models are validated by comparison against two sets of transient experimental data generated at the CO2 capture pilot plant realized and operated at the Buggenum IGCC power station in the Netherlands. The model predictions satisfactorily reproduce the dynamic performance of the pilot plant considering the main process variables, such as pressures, flow rates and compositions. One of the results of this work is that, in case of physical absorption of CO2 a well-tuned, equilibrium-based absorber model is able to accurately predict transient operation. The validated process models enable process and control system design aiming at improvement of transient performance of the pre-combustion capture unit.

Business Intelligence Solutions for Wind Power Plants Operation

The European Union energy strategies imply significant changes in the power systems. These should contribute to sustainable development and protection of the environment by enabling the EU to achieve its targets set in the third package of legislative proposals for electricity and gas markets. Renewable energy sources (RES) in Romania have been encouraged since 2007 and this lead to a large volume of projects. It took several years to have the first MW installed in wind power plants (WPP). Nowadays, the installed wind power in Romania is about 2642 MW, most of them (about 85%) being concentrated in the south-eastern part of the country. Based on recorded data during four years in Romania, a couple of analyses have been performed. They contribute to a better integration of wind energy into power systems. This paper will describe how business intelligence solutions are applied on data regarding wind power plants operation and main conclusions that could be drawn.