Narrow Results

This paper presents a novel optimal utilization of hybrid wind–solar system as dynamic voltage restorer (DVR) for voltage sag, voltage swell, outage and unbalanced voltage mitigation. Besides the voltage regulation, the proposed DVR reduces the energy consumption from the three phase utility grid by utilizing the rated inverter capability after excessive or equal real power generation to the load demand during both day time and night time. It reduces the energy consumption from the three phase utility grid. However, the reduction of energy consumption is always desirable for the reduction of panel tariff and electricity demand. The proposed system was simulated using MATLAB-SIMULINK in which the input parameters were selected from the metrological data of the selected location to validate the advantage of the proposed system.

The seismic performance of monopiled offshore wind turbine (OWT) structures was evaluated numerically. The aim was to analyze offshore wind farm sites on complicated layered seabed with high seismicity. Following pile soil analysis (PISA) model, three-dimensional (3D) numerical evaluations were undertaken for two separate locations under two independent seismic events. The effects of pile diameter, depth, site impact owing to transverse soil layering, uni-directional and multi-directional seismic loading and seismic acceleration magnitude are presented. Dynamic impedance depth variation and site response analysis via lateral displacement, lateral soil response and Fourier response amplitude are explored in frequency and time domain. In a seismic zone with stratified soil, pile diameter has a greater influence. Variations in soil profile affect wind turbine performance and seismic sensitivity. This research will give a strong platform for later studies to recommend a safe wind farm site based on simulation results.

In this paper we establish how effectively EIA is currently utilised in the deployment of onshore and offshore wind energy in the United Kingdom (UK) and Germany. In this context, the quality of EIA documentation and the coverage of a range of key EIA aspects of 20 developments are evaluated. Furthermore, the impact of EIA on decision making is established, based on opinions of decision makers and other stakeholders. We find that whilst there are certain weaknesses, overall EIA information is central to decision making, and EIA is resulting in major project modifications. Our results differ from the findings of most previous studies which usually observed a moderate impact on decision making only.

During this rapid development of wind energy aiming to combat climate change worldwide, there is greater need to avoid, reduce, and compensate for impacts on wildlife: Through the effective use of mitigation, wind energy can continue to expand while reducing impacts. This is a first broad step into discussing and understanding mitigation strategies collectively, identifying the current state of knowledge and be a beneficial resource for practitioners and conservationists. We review the current state of published knowledge, both land-based and offshore, with a focus on wind energy–wildlife mitigation measures. We state measures and highlight their objective and discuss at which project stage it is most effective (e.g. planning, construction, and operation). Thereafter, we discuss key findings within current wind energy mitigation research, needing improved understanding into the efficacy of wildlife mitigation as well as research into the cost aspects of mitigation implementation. This paper is divided into two articles; Part 1 focuses on mitigation measures during planning, siting, and construction, while Part 2 focuses on measures during operation and decommissioning.

During this rapid development of wind energy aiming to combat climate change worldwide, there is greater need to avoid, reduce, and compensate for impacts on wildlife: Through the effective use of mitigation, wind energy can continue to expand while reducing impacts. This is a first broad step into discussing and understanding mitigation strategies collectively, identifying the current state of knowledge and be a beneficial resource for practitioners and conservationists.

We review the current state of published knowledge, both land-based and offshore, with a focus on wind energy–wildlife mitigation measures. We state measures and highlight their objective and discuss at which project stage it is most effective (e.g. planning, construction, operation). Thereafter, we discuss key findings within current wind energy mitigation research, needing improved understanding into the efficacy of wildlife mitigation as well as research into the cost aspects of mitigation implementation. This review is divided into two articles; Part 1 focuses on mitigation measures during planning, siting, and construction, while Part 2 focuses on measures during operation and decommissioning.

Considering rapid development and emerging new challenges of China's wind energy development, this paper summarizes and analyzes five critical problems. First, according to an economic potential assessment, if the feed-in tariff is set 0.60 Yuan/kWh, the economic potential of wind electricity of China will reach 6.63PWh, it could meet as much as 2/3 of total power demand by 2030, thus the targeted wind power proportion in future high renewable energy penetration can be achieved. Second, wind energy is abundant but little consumed in Northwest, Northeast and North China while it is insufficient in South and East of China, where grid-connection condition is well. Due to this reverse distribution pattern of wind power endowment and consumption in China, grid-connection transmission must be strengthened in the future, particularly the West–East and North–South power transmission projects must be pushed forward. Third, to address the issue of increasing wind energy curtailment in Northeast, Northwest and North China, stimulating local consumption of wind power by multiple ways is a possible solution in the short term, however, in the medium and long run, it is necessary to accelerate the construction of Ultra-High Voltage power grid in order to expand power transmission to other provinces and regions. Fourth, a new electricity market mechanism should be established as the fundamental measure of promoting new energy development, while green certificate trading market and carbon trading market will form the basis for such market mechanism in the long run. Fifth, though wind power development can bring multiple benefits to economy, employment, and environment, large-scale wind power development will, to some extent, affect local and regional climate. As global warming continues, the wind power resource distribution of China and the world may experience significant changes.

Modeling wind speed time series (WSTS) has important implications in wind energy studies. This paper provides a method to modeling WSTS with continuous state markov chain (CSMC). The basic feature of the method is describing WSTS in continuous state space, which can reduce the number of parameters and avoid the loss of information. Case studies are used to illustrate the capabilities of the proposed method. The results prove that the method can offer satisfactory fit for both probability distribution and temporal dependence. The comparison shows that the proposed method outperforms discrete state markov chain in terms of accuracy and simplicity.

This work presents a vector control (VC) of an emerging brushless doubly-fed reluctance (BDFRG) technology for large wind turbine applications. The BDFRG has been receiving increasing attention due to its low operation and maintenance costs afforded by the use of partially-rated power electronics, and the high reliability of brushless assembly, while offering performance competitive to its traditional slip-ring counterpart, the doubly-fed induction generator (DFIG). A robust VC strategy has been developed for a custom-designed BDFRG fed from a conventional ‘back-to-back’ IGBT converter. Preliminary studies have evaluated the algorithm under the power factor control (PFC) conditions which allow the enhanced efficiency of the generator-converter set and the entire wind energy conversion systems (WECS).

The core of the present work focuses on the detailed analysis on the wind power potential of the Ponza Island. The results have been obtained thanks to the use of advanced software tools developed specifically for the purpose of wind data elaboration. The main output of this analysis is a detailed map representing the wind farm locations and an estimation of 4,5 MW of installed wind power equivalent to an annual production of 9 GWh of electric power (that is the 90% of the annual demand of the entire island). Finally the work presents an innovative way of project-financing making the whole project feasible and easy to adopt for the public administration.

Research for sail-assisted technologies should be strengthened for promoting the development of sail assisted project. This paper mainly investigates the sail structure design, dynamic performance and the sail driving control strategy for the large ocean-going sail-assisted ship. For the circular thin optimal sail of one 48000 DWT bulk carrier, the aerodynamic characteristics was analyzed and the sail area was selected through combining with the model parameters from the results of the experimental analysis. Then, the torque for each set of sail was roughly calculated. According to the actual requirements of the sail driving control for energy-saving and driving-safety the hydraulic control is feasible. Compared two traditional hydraulic control systems, the improvement scheme of hydraulic control with variable-frequency technology was further proposed which is a more optimal control method for sail driving control of large ocean-going ships.

In this paper, a pitch angle controller is designed based on adaptive control theory to guarantee steady generator power output while reducing the mechanical loads at above rated wind speed. A non-affine model of the pitch regulated variable-speed wind turbine is built to formulate complicated aerodynamics. The adaptive pitch angle controller assures wind energy conversion system of uniformly bounded transient response in the presence of rapidly changing wind speed, in addition to stable generator angle speed. Without the loss of system robustness, we can improve the performance bounds of adaptive controller by increasing the adaptation rate. Simulation results on GH Bladed software package show that more steady operating output power is obtained by the adaptive controller compared to the traditional pitch angle controller adopted in industry.

This paper deals with nonlinear model based adaptive power capture control of wind energy conversion systems (WECS) using online approximator (OLA) in low-speed region. Compared with the traditional linear techniques valid only around an operating point, which may result in poor system performance and low reliability since the operating point may change with time due to the stochastic operating conditions, the developed controller in this paper is totally a nonlinear one capable of covering the whole operating range. In addition, with the aid of a two-layer neural network, we waive the requirement of system dynamics and aerodynamic torque. Furthermore, the weights of neural network are updated in an online manner, which means that no off-line training is needed. Finally, the effectiveness and merits of our proposed controller are verified on a 1.5 MW three-blade wind turbine using the FAST (Fatigue, Aerodynamics, Structures, and Turbulence) code developed by the National Renewable Energy Laboratory (NREL).

The paper studies automobile styling mode and designing way by the character of new energy-wind energy and solves the problems on how to grasp the characters of newenergy automobile styling and the application of new energy. It analyzes the relationship between wind energy conversion and styling in the automobile styling design through combining air flow principle and practical cases, realizes the practical application of the regenerating wind energy character in automobile headstock and body styling design of the new-energy automobile effectively, and advances the balance between aesthetics and aeromechanics in the automobile styling and its corresponding solutions.

At the latest public reports of the Intergovernmental Panel on Climate Change (IPCC) or the UN Climate Change Conferences, a socio-political discussion arose over possible harmful impacts of fossil energy sources for the global climate and our environment. Also, due to the still unsolved problem of radioactive waste disposal and diverse tragic incidents in nuclear power plants within the last years, many experts criticize the use of nuclear power as a non-sustainable energy source. With regards to the finiteness and environmental harmfulness of fossil energy sources and the danger of nuclear material for present and future generations, the importance and popularity of renewable energies in Germany increases continuously. In particular, Wind Energy influences the success story of renewable energiesover the last years.

In addition to positive environmental, CO²-saving aspects, Wind Energy can also be supportive and even fundamental in terms of growth and development for Germany's economy. Economic growth indicators such as a rising revenue development, increasing employment rate or a high export volume are representatives for the economic importance of renewable energies and wind energy in particular.