Master Degree / Yüksek Lisans Tezleri

Permanent URI for this collectionhttps://hdl.handle.net/11147/3008

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Subject: search.filters.subject.Wind farm

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Now showing 1 - 3 of 3
  • Master Thesis
    Wind Turbine Control Via Power Measurements in Complex Terrain
    (01. Izmir Institute of Technology, 2022) Dirik, Deniz Gökhan; Bingöl, Ferhat
    This work presents an approach to the assessment of wind farm yaw control to utilize wake steering in complex terrain based on power measurements. Aerodynamic interactions between closely spaced wind turbines reduce the power output significantly. The standard wind turbine control strategy currently focuses on optimizing the wind turbines individually. However, there is growing evidence that these wake losses can be improved by optimizing for aerodynamic interactions between the turbines. In a case study, an assessment of wake steering gain and optimum yaw offset angles for each wind turbine are simulated for an operational wind farm. Wake losses are simulated for the wind farm and are validated using historical power measurements. Data analysis procedures for implementing operational wind farm data for the wake steering approach are described. Optimum yaw offset angles are calculated in simulations using operational data. A lookup table is generated for the optimum yaw angles required for each wind direction and speed bin. Using 5-year-long operational data, an average of 0.48% wake losses are calculated for the site. FLORIS simulations suggest 9.6% possible power improvement in wake losses using the optimum yaw offset angles. Using SCADA measurements for potential wake steering assessment allows rapid assessment and implementation without requiring expensive and year-long LIDAR or meteorological mast tower measurements.
  • Master Thesis
    Coupled Wake and Blockage Modelling for a Wind Farm
    (Izmir Institute of Technology, 2022) Çam, Janset Betül; Bingöl, Ferhat
    One of the significant reasons for the power loss in wind farms is the wake effect. Therefore, the wake effect is crucial for designing a wind farm. However, only wake modeling is not sufficient to explain power losses. Wake is the turbulent, complex, and relatively weak flow behind the wind turbine. The wake effect is not required for the front row turbines in wind farms, and the wake model cannot be applied. It is assumed that the wind farm directly encounters the free stream wind speed. However, the blockage effect, also known as the induction zone effect, is observed at the front of the wind turbines. Due to this effect, the wind farm encounters a lower wind speed than the free-stream wind speed. This situation reduces the accuracy of the Annual Energy Production (AEP) calculation in wind farms. The motivation of this study is to obtain an improved coupled wake and blockage model that converges to the accurate SCADA data of a wind farm more than the wakeonly or blockage-only models. This study applies seven wake and six blockage models to the wind farm. The similarities and differences between the coupled models and the wind farm SCADA data and their reasons are discussed.
  • Master Thesis
    Gis-Based Multi-Criteria Approach for Land-Use Suitability Analysis of Wind Farms: the Case Study of Karaburun Peninsula, Izmir,-Turkey
    (Izmir Institute of Technology, 2015) Sediqi, Khwaja Jawid; Özdemir, Semahat; Saygın, Mustafa Ömür; Saygın, Mustafa Ömür; Özdemir, Semahat
    This study presents a GIS-based multi-criteria approach to identify the most preferred or suitable site for wind farms development in Karaburun Peninsula, İzmir. Criteria for analysis have been identified based on literature review and experts’ opinions. The selected criteria include environmental, technical, and economic as well as social factors. In order to estimate the weights or relative importance of the criteria, the pairwise comparison method in the context of Analytic Hierarchy Process (AHP) is implemented. The overall suitability of the study area is determined through the Weighted Overlay method, which is a sufficient weighted approach in geographical information system (GIS) environment. The outcome or suitability map is classified into five scored classes from the most suitable to less suitable and restricted area. On the whole, as the selection of optimal site for the wind farm development is a multi-dimensional process, this thesis intends to consider the following three significant subjects; (a) evaluating and identifying the most influential criteria for land suitability analysis of wind farms, (b) applying AHP as a multi criteria decision-making method to determine the criteria weights, (c) utilizing GIS as a tool to overlay the overall criteria and consequently to identify the potentially suitable location for the wind farms development. Regarding to the above mentioned, eight the most influential available criteria, which are consisted of wind potential, distance from preservation area, distance from settlements, forest, slope, elevation, distance from roads, and agriculture area are identified. Base on pairwise comparison different weights for each criterion is determined. Finally, by using GIS the suitability map for the study area is provided and the result compared with the existing wind farm locations.