Wind generation has become the most important alternate energy source and has experienced increased progress in India during the past decade. While it has great potential as an alternative to less environmentally friendly energy sources, there are various technical challenges that cause wind to be considered negatively by many utilities. Wind energy conversion systems suffer from the fact that their real power generation is closely dependent on the local environmental conditions.
The Doubly Fed Induction Generator (DFIG) based wind turbine with variable-speed variable-pitch control scheme is the most popular wind power generator in the wind power industry. This machine can be operated either in grid connected or standalone mode.
In this thesis, a detailed electromechanical model of a DFIG-based wind turbine connected to power grid as well as separately operated wind turbine system with different sub-systems is developed in the MATLAB/SIMULINK environment and its equivalent generator and turbine control structure is realized. In this regard following configurations have been considered:
• DFIG with Battery storage sub-system
• DFIG with Buck-Boost converter
• DFIG with transformer
• DFIG with 3-winding transformer
Addition of battery storage and buck-boost converter sub-systems into the system enables not only dispatching of generator power but also decreases the variability in their reactive power requirements. The full control over both active and reactive power is possible by the use of transformer between DFIG and rotor side converter.
The steady state behavior of the overall wind turbine system is presented and the steady state reactive power ability of the DFIG is analyzed. It has been shown that major part of the reactive power should be supplied from rotor side converter to reduce the overall rating of the generator.
The DFIG with above mentioned sub-systems is connected to grid. The total harmonic distortion analysis and efficiency are carried out. It is found that DFIG with transformer in between machine and rotor side converter has lowest THD (2.29%) and DFIG with 3-winding transformer has maximum efficiency (above 93%).
Inhaltsverzeichnis (Table of Contents)
- Chapter 1: Introduction
- Chapter 2: Literature Review
- Chapter 3: System Modeling and Control
- Chapter 4: Simulation and Results
- Chapter 5: Conclusion
Zielsetzung und Themenschwerpunkte (Objectives and Key Themes)
This thesis aims to develop and analyze a detailed electromechanical model of a Doubly Fed Induction Generator (DFIG)-based wind turbine connected to a power grid. The study investigates the performance of the DFIG with various subsystems, including battery storage, buck-boost converters, and different transformer configurations. The overall goal is to evaluate the effectiveness of these configurations in improving power quality and efficiency.
- Modeling and simulation of a DFIG-based wind turbine system.
- Analysis of the impact of different subsystems (battery storage, buck-boost converter, transformers) on system performance.
- Evaluation of the steady-state behavior and reactive power capabilities of the DFIG.
- Assessment of total harmonic distortion (THD) and overall system efficiency.
- Determination of optimal configuration for improved power quality and efficiency.
Zusammenfassung der Kapitel (Chapter Summaries)
Chapter 1: Introduction: This chapter provides a general introduction to wind energy, highlighting its importance as an alternative energy source and the challenges associated with its integration into power grids. It introduces the DFIG-based wind turbine as a popular choice in the wind power industry and outlines the scope of the thesis, focusing on the modeling and analysis of DFIG systems with various subsystems to enhance performance and stability.
Chapter 3: System Modeling and Control: This chapter presents the detailed electromechanical model of the DFIG-based wind turbine system developed in the MATLAB/SIMULINK environment. It describes the modeling of the DFIG, the wind turbine, and the various subsystems (battery storage, buck-boost converter, transformers). The chapter also details the control strategies employed for the converters and the DFIG, aiming to achieve optimal power control and reactive power compensation. The specific control objectives for each component are clearly outlined and justified, forming the foundation for the simulations detailed in later chapters.
Chapter 4: Simulation and Results: This chapter presents the simulation results obtained from the developed model. It analyzes the steady-state behavior of the DFIG system with different subsystems and assesses their impact on power quality and efficiency. The analysis includes a detailed examination of the reactive power capabilities of the DFIG and the effectiveness of different control strategies in mitigating power fluctuations and improving overall system performance. The results are presented and analyzed in detail, supporting the conclusions drawn in the final chapter.
Schlüsselwörter (Keywords)
Doubly Fed Induction Generator (DFIG), wind turbine, wind energy conversion system, grid integration, battery storage, buck-boost converter, transformer, reactive power compensation, total harmonic distortion (THD), power quality, MATLAB/SIMULINK, system modeling, control strategies.
Frequently Asked Questions: Analysis of a DFIG-Based Wind Turbine System
What is the overall goal of this thesis?
The thesis aims to develop and analyze a detailed electromechanical model of a Doubly Fed Induction Generator (DFIG)-based wind turbine connected to a power grid. It investigates the performance of the DFIG with various subsystems (battery storage, buck-boost converters, and different transformer configurations) to evaluate their effectiveness in improving power quality and efficiency.
What are the key themes explored in this thesis?
Key themes include modeling and simulation of a DFIG-based wind turbine system, analyzing the impact of different subsystems on system performance, evaluating the steady-state behavior and reactive power capabilities of the DFIG, assessing total harmonic distortion (THD) and overall system efficiency, and determining the optimal configuration for improved power quality and efficiency.
What systems are included in the model of the DFIG-based wind turbine?
The model includes the DFIG, the wind turbine itself, battery storage, a buck-boost converter, and different transformer configurations.
What software was used for modeling and simulation?
MATLAB/SIMULINK was used for the modeling and simulation of the DFIG-based wind turbine system.
What are the main chapters and their content?
Chapter 1 (Introduction): Provides a general introduction to wind energy and the DFIG. Chapter 2 (Literature Review): (Not explicitly detailed in the preview). Chapter 3 (System Modeling and Control): Presents the detailed electromechanical model of the DFIG system in MATLAB/SIMULINK, including descriptions of the DFIG, wind turbine, and subsystems, along with the control strategies. Chapter 4 (Simulation and Results): Presents and analyzes simulation results, examining the steady-state behavior, reactive power capabilities, and the impact of different subsystems on power quality and efficiency. Chapter 5 (Conclusion): (Not explicitly detailed in the preview).
What key performance indicators (KPIs) are analyzed?
Key performance indicators include reactive power capabilities, total harmonic distortion (THD), and overall system efficiency.
What are the key words associated with this thesis?
Doubly Fed Induction Generator (DFIG), wind turbine, wind energy conversion system, grid integration, battery storage, buck-boost converter, transformer, reactive power compensation, total harmonic distortion (THD), power quality, MATLAB/SIMULINK, system modeling, control strategies.
What is the purpose of the different subsystems (battery storage, buck-boost converter, transformers)?
These subsystems are included to investigate their impact on the overall performance, stability, and power quality of the DFIG-based wind turbine system. The aim is to identify optimal configurations for improved efficiency and power quality.
- Quote paper
- Akshay Kumar (Author), 2014, DFIG-based Wind Power Conversion System Connected to Grid, Munich, GRIN Verlag, https://www.grin.com/document/279068
