In this book shows a novel control approach of a three phase grid connected wind energy conversion system, incorporating a maximum power point tracker for dynamic active power generation jointly with reactive power compensation of distribution utility systems has been presented. Thus the five level multilevel inverter topology were chosen based on what has gone before, even if that topology may not be the best choice for the application. Several multilevel voltage source inverters and their modulation topologies are introduced. The cascaded-inverter with separated dc sources is discussed in detail with results to verify the proposed concepts. The improved capabilities of the grid-connected WECS to rapidly exchange active power with the electric system, simultaneously and independently of the reactive power exchange, permit to greatly enhance the operation and control of the electric system.
In this book a dynamic models have been developed for the following: variable speed wind energy conversion systems and power electronic interfacing devices. These dynamic models are suitable for both detailed fast transient and large time scale performance evaluation studies. They can be used to expedite the research processes in the related alternative energy areas, such as system control, performance optimization studies and diagnosis. One of the original points is that this work is the use of a new the fault detection and isolation method (FDI). The proposed method avoids the exploration of all the combinations for its application to the diagnostic of this system operation. The causal paths are used to generate the analytical redundancy relations (ARR) at each computation step based on the constitutive and structural junction relations. This is shown through an algorithm for monitoring the system by sensors placements on the corresponding bond graph model.
The primary task of a wind turbine is to generate electricity from the wind and to supply the produced power to the user. Control of a wind turbine is an integral part of the wind power generation system for proficient operation of the wind turbine, to ensure the maximum power production and finally, maximum energy capture from a wind turbine system. In order to avoid problems at installation, it is required to test the power electronics and study the performance of the controller in a laboratory environment. The aim of this book is therefore to propose and validate maximum power point control strategies for wind turbine and most importantly, to develop a prototype of a small wind energy conversion system that emulates the steady state and dynamic behavior in a laboratory environment.
The destructive phenomenon of global warming is developing to more critical and obvious index that causes the melting of polar ice caps and higher sea levels resulting in less land for an increasing population, along with the severe changes in climate. Essentially, the growth of this harsh trend is primarily due to the increase of the greenhouse gases concentration from burning of the fossil fuels. So, traditional approach of producing energy to fulfill the human demand is no longer appropriate; meanwhile, inception of wind energy electrical power systems will be the alternative technologies to bring a better future for all mankind. This book provides a comprehensive explanation of the wind energy potential evaluation technique and a robust sensorless MPPT controller for variable speed PMSG wind turbine stand-alone system modeled in Matlab/Simulink environment which shows the feasibility of the technologies compared to the conventional electrical power generation. The study of the WECS will assist the professionals in wind electrical power generation system, global academic researchers, industrial engineers, or those who may consider in implementing this system
Wind energy conversion systems are now occupying important space in the research of renewable energy sources. There is a need for further research on Wind Generators and Power Integration Topologies. In this work we are using Permanent Magnet Synchronous Generator (PMSG) for wind power generation and the behavior of PMSG when subjected to different wind speeds is being studied in MATLAB. This also provides a comparison of different power converter topologies used in Wind Energy Conversion System (WECS).
In the time of current trend of increasing energy consumption, the wind-power engineering may compensate considerable part of required electric energy. Rapid wind-power engineering development is considered to be one of the important sources of human need satisfaction. Conventional wind turbine control strategies are dedicated to ensure high energy conversion efficiency under varying wind conditions. The challenge in wind power control engineering is to design an adaptive wind turbine control strategy, which provides the dynamic system stability and the effectiveness of energy conversion. The aim of this book is to design and implement the control algorithm, which implies the electromagnetic torque control in order to adapt the rotor speed and keep high energy conversion efficiency. Wind turbine operation is considered in the partial-load regime. The stability of the purposed control system is studied using linear control theory concepts. The effectiveness of the wind energy conversion is proved by the simulation results in MATLAB Simulink environment.
In the small wind energy domain, the existing knowledge of the system of a Permanent Magnet Generator (PMG)-based small wind turbine system design and performance is quite rich. In sharp contrast, studies with emphasis on the system of Wound Rotor Induction Generator (WRIG)-based small wind turbine system are very few. However, despite such rapid growth of the PMG-based system, it is difficult to predict the future for both systems. This is because ideas borrowed from other fields or other applications could have profound effects on future penetration. In this context, this research presents a performance and reliability investigation of both systems with a special focus on the power electronics and led the future of wind energy conversion system in an unique direction.
The use of hydrogen storage enables long term energy storage in hybrid wind-fuel cell energy system. The aim of this research is to study the feasibility of a wind-hydrogen energy system that produces electricity to households,health post, grinding facility, schools and water pumps in rural areas. The system consists mainly of wind turbines, fuel cells, electrolyzers and hydrogen tanks. The wind resource in the country was studied after selecting five representative cities that are geographically different. These are Addis Ababa, Nazareth, Mekelle, Debre Brehan and Dire Dawa.The system The best system is chosen for each location based on net present cost(NPC) and detail analysis of system performance. The results indicate that the system enables high renewable fraction with up to 8 days of energy autonomy only at moderate increase in NPC over a wind-diesel-battery system.
Solar energy, radiant light and heat from the sun, has been reined by humans since ancient times using a range of ever-evolving technologies. Solar radiant energy accounts for most of the usable renewable energy on earth. Photovoltaic (PV) is a method of generating electrical power by converting solar radiation into direct current electricity using semiconductors that exhibit the photovoltaic effect.The tracking process of maximum power point is called maximum power point tracking (MPPT). The concept of Maximum Power Point Tracking is to be implemented which results in appreciable increase in the efficiency of the Photovoltaic System. Different schemes of MPPT algorithms such as Perturb and Observe.To overcome the difficulties of commonly used MPPT methods a unique controller called fuzzy logic controller is implemented.In this paper a novel back propagation neural network based MPP controller is proposed and it is shown that it can track the MPP more accurately than fuzzy logic based controller.Due to the conventional inherent nature of neural network based controller, it shows no oscillation around the MPP and hence no power loss owing to this fact.
Due to the growing demand for electrical energy and environmental impact such as global warming and pollution, photovoltaic (PV) energy generation system has been considered as a technological option for generating clean energy. The advantage of PV system is that it is pollution free, but it still has relatively low conversion efficiency from solar irradiation to electric power. Power delivered by the PV system depends on several environmental factors such as lighting conditions, temperature and shading. The nonlinear characteristic of PV array, the fluctuating output power which varies with temperature and irradiation and losses in power conditioner devices are among the drawbacks of PV systems. An important consideration in increasing the efficiency of PV systems is to operate the system approximate to the maximum power point (MPP). This book discussed a new high performance maximum power point tracking (MPPT) controller by using a new boost converter and a new intelligent MPPT algorithm.