Modeling Analysis And Enhancement Of The Performance Of A Wind Driven Dfig During Steady State And Transient Conditions

Recently, wind electrical power systems are getting a lot of attention since they are cost competitive, environmentally clean, and safe renewable power source as compared with the fossil fuel and nuclear power generation. A special type of induction generator, called a doubly fed induction generator (DFIG), is used extensively for high-power wind applications. They are used more and more in wind turbine applications due to the ease of controllability, the high energy efficiency, and the improved power quality.This research aims to develop a method of a field orientation scheme for control both, the active and the reactive powers of a DFIG that are driven by a wind turbine. Also, the dynamic model of the DFIG, driven by a wind turbine during grid faults, is analyzed and developed, using the method of symmetrical components. Finally, this study proposes a novel fault ride-through (FRT) capability with a suitable control strategy (i.e. the ability of the power system to remain connected to the grid during faults).

This essential book examines the main problems of wind power integration and guides the reader through a number of the most recent solutions based on current research and operational experience of wind power integration.

Power Electronics Handbook, Fifth Edition delivers an expert guide to power electronics and their applications. The book examines the foundations of power electronics, power semiconductor devices, and power converters, before reviewing a constellation of modern applications. Comprehensively updated throughout, this new edition features new sections addressing current practices for renewable energy storage, transmission, integration, and operation, as well as smart-grid security, intelligent energy, artificial intelligence, and machine learning applications applied to power electronics, and autonomous and electric vehicles. This handbook is aimed at practitioners and researchers undertaking projects requiring specialist design, analysis, installation, commissioning, and maintenance services. Provides a fully comprehensive work addressing each aspect of power electronics in painstaking depth Delivers a methodical technical presentation in over 1500 pages Includes 50+ contributions prepared by leading experts Offers practical support and guidance with detailed examples and applications for lab and field experimentation Includes new technical sections on smart-grid security and intelligent energy, artificial intelligence, and machine learning applications applied to power electronics and autonomous and electric vehicles Features new chapter level templates and a narrative progression to facilitate understanding

WIND ENERGY GENERATION WIND ENERGY GENERATION MODELLING AND CONTROL With increasing concern over climate change and the security of energy supplies, wind power is emerging as an important source of electrical energy throughout the world. Modern wind turbines use advanced power electronics to provide efficient generator control and to ensure compatible operation with the power system. Wind Energy Generation describes the fundamental principles and modelling of the electrical generator and power electronic systems used in large wind turbines. It also discusses how they interact with the power system and the influence of wind turbines on power system operation and stability. Key features: Includes a comprehensive account of power electronic equipment used in wind turbines and for their grid connection. Describes enabling technologies which facilitate the connection of large-scale onshore and offshore wind farms. Provides detailed modelling and control of wind turbine systems. Shows a number of simulations and case studies which explain the dynamic interaction between wind power and conventional generation.

This thesis presents a comprehensive study on the operation, principles and theory of wind farms consisting of doubly-fed induction (DFIG) and fully-rated converter (FRC) wind generators working together in a hybrid arrangement. The main objective of this study is to develop control strategies for the hybrid arrangement of wind turbines in order to improve the grid code compliance of the overall wind farm by exploiting the unique characteristics of both technologies to support each other in case of a fault happening. As a result, this thesis presents a novel control strategy for fully rated converter wind generators to improve the fault ride through capabilities of DFIG wind turbines during an AC voltage sag. The developed controller enables the creation of an environment where the FRC and DFIG technologies coexist for the purpose of compliance of grid code requirements. This type of environment can be created in both new wind farm developments and in already deployed DFIG-based wind farms where the addition of FRCs results in the overall improvement of the grid code compliance of the wind farm.The novel controller developed in this thesis uses the FRC to supply reactive power to the hybrid wind farm network during faults with the objective of reducing the magnitude of the voltage dip. This has positive effects in DFIG rotor speed and DC voltage variables during and after the fault period. These variables, as explained in the thesis, play a crucial role in stabilising the dynamic fault ride through capabilities of the turbine. Additionally, the novel controller developed in this thesis does not compromise the integrity of the FRC system.This thesis also contributes to the investigation of hybrid wind farms connected to the main grid using voltage source converter high-voltage direct current (VSC-HVDC) as a mean to increase renewable energy penetration and transmission capacity without affecting voltage stability or power quality of the specific case of the Great Britain's (GB) network. One main control approach was investigated on the sending-end converter to integrate offshore wind power from hybrid network where all generated power is injected to the point-to-point DC link with a stiff AC bus at the wind farm network. Additionally, two possible connection topologies of future VSC-HVDC were investigated for steady state and transient conditions. The operation of a multi terminal DC network (MTDC) for hybrid offshore wind farms is analysed with power flow studies of a 5-terminal MTDC model regulated by droop control.Finally, this thesis investigates three VSC-HVDC connections schemes designed to transfer 2.4GW of power from two separate Dogger Bank wind farms to the GB grid, in terms of the investment costs, controllability and reliability against expected scenarios. The benefits and drawbacks of all three scenarios are highlighted. These include the benefits of auxiliary cables on AC and DC site of the multi-terminal connections.

Master's Thesis from the year 2013 in the subject Engineering - Power Engineering, grade: none, - (Faculty of engineering-Minia university - Electrical engineering department), course: Electrical engineering (Renewable energy), language: English, abstract: Wind electrical power systems are recently getting lot of attention, because they are cost competitive, environmental clean and safe renewable power source, as compared with fossil fuel and nuclear power generation. A special type of induction generator, called a doubly fed induction generator (DFIG), is used extensively for high-power wind applications. They are used more and more in wind turbine applications due to ease controllability, high energy efficiency and improved power quality. This thesis aims to develop a method of a field orientation scheme for control both the active and reactive powers of a DFIG driven by a wind turbine.The proposed control system consists of a wind turbine that drives a DFIG connected to the utility grid through AC-DC-AC link. The main control objective is to regulate the dc link voltage for operation at maximum available wind power.This is achieved by controlling the and axes components of voltages and currents for both rotor side and line side converters using PI controllers. The complete dynamic model of the proposed system is described in detail. Computer simulations have been carried out in order to validate the effectiveness of the proposed system during the variation of wind speed. The results prove that, better overall performances are achieved, quick recover from wind speed disturbances in addition to good tracking ability. Generally, any abnormalities associated with grid asymmetrical faults are going to affect the system performance considerably. During grid faults, unbalanced currents cause negative effects like overheating problems and mechanical stress due to high torque pulsations that can damage the rotor shaft, gearbox or blade assembly. Therefore, the dynamic mo

An essential reference to the modeling techniques of wind turbine systems for the application of advanced control methods This book covers the modeling of wind power and application of modern control methods to the wind power control—specifically the models of type 3 and type 4 wind turbines. The modeling aspects will help readers to streamline the wind turbine and wind power plant modeling, and reduce the burden of power system simulations to investigate the impact of wind power on power systems. The use of modern control methods will help technology development, especially from the perspective of manufactures. Chapter coverage includes: status of wind power development, grid code requirements for wind power integration; modeling and control of doubly fed induction generator (DFIG) wind turbine generator (WTG); optimal control strategy for load reduction of full scale converter (FSC) WTG; clustering based WTG model linearization; adaptive control of wind turbines for maximum power point tracking (MPPT); distributed model predictive active power control of wind power plants and energy storage systems; model predictive voltage control of wind power plants; control of wind power plant clusters; and fault ride-through capability enhancement of VSC HVDC connected offshore wind power plants. Modeling and Modern Control of Wind Power also features tables, illustrations, case studies, and an appendix showing a selection of typical test systems and the code of adaptive and distributed model predictive control. Analyzes the developments in control methods for wind turbines (focusing on type 3 and type 4 wind turbines) Provides an overview of the latest changes in grid code requirements for wind power integration Reviews the operation characteristics of the FSC and DFIG WTG Presents production efficiency improvement of WTG under uncertainties and disturbances with adaptive control Deals with model predictive active and reactive power control of wind power plants Describes enhanced control of VSC HVDC connected offshore wind power plants Modeling and Modern Control of Wind Power is ideal for PhD students and researchers studying the field, but is also highly beneficial to engineers and transmission system operators (TSOs), wind turbine manufacturers, and consulting companies.

Rapid deployment of wind and solar energy generation is going to result in a series of new problems with regards to the reliability of our electrical grid in terms of outages, cost, and life-time, forcing us to promptly deal with the challenging restructuring of our energy systems. Increased penetration of fluctuating renewable energy resources is a challenge for the electrical grid. Proposing solutions to deal with this problem also impacts the functionality of large generators. The power electronic generator interactions, multi-domain modelling, and reliable monitoring systems are examples of new challenges in this field. This book presents some new modelling methods and technologies for renewable energy generators including wind, ocean, and hydropower systems.