Wind Power Technology Research Articles

The benefits and burdens of wind power systems in reaching China’s renewable energy goals: Implications from resource and environment assessment

Recognizing the economy’s growing reliance on global energy landscape transformation on wind power deployment, as well as the general reality that renewable facilities require lower operational but higher up-front inputs than fossil-based power systems, this paper focuses on the life-cycle burdens of wind power systems and their substitution benefits compared with coal-fired power systems. The estimation considers the consumption of nonrenewable sources of energy, emissions of greenhouse gases, and other environmental resource factors that have received significantly less research attention, such as industrial land use, water use, PM2.5, SO2, NOX, and Hg emissions. The scope of this study differs from earlier ones in that it includes a comprehensive description of all the equipment, materials, and services used, as opposed to earlier studies that either omit crucial supporting infrastructure or just focus on the plant’s physical structure as its primary materials. Results based on a typical plant in China show that the state-of-the-art onshore wind power systems can provide significant reductions in nonrenewable energy use (9.2 MJ/kWh) and GHG emissions (782.8 GtCO2/kWh). To produce an equivalent amount of electricity, wind power systems require more than three times industrial land use and almost one-third of industrial water use of that for traditional coal-fired power systems. The avoided SO2, Hg, PM2.5, and NOX emissions per unit of electricity generation account for 60.6%-89.3% of the total air pollution emissions induced by supercritical coal-fired power systems. By integrating 3797 operating plant-specific data and fixed-point wind energy information, this study scales up results of the single plant to a country level. The macro picture implies different opportunities born by wind power systems in easing multiple resource and environmental pressures, highlighting the significance of designing hierarchical strategies to improve penetration levels of wind power. By 2050, cumulative climate benefits obtained from onshore wind power technology are predicted to reach 74.2 Gt CO2, achieving around 17.2%-45.5% of the national carbon-neutral goal.

Study on the Ratio and Model Test of Similar Materials of Heavily Weathered Granite.

To study the bearing characteristics of rock-socketed single piles on the southeast coast of Fujian Province, we conducted similar material ratio tests and single pile model tests. Initially, based on the mechanical parameters of strongly weathered granite, 10 groups of similar material samples were prepared using iron concentrate powder, barite powder, and quartz sand as aggregates, with rosin and alcohol as the cementing agents and gypsum as the modulating agent. Through triaxial testing and range and variance analysis, it was determined that the binder concentration has the most significant impact on the material properties. Consequently, Specimen 1 was selected as the simulation material. In the model test, the strongly weathered granite stratum was simulated using the ratio of Specimen 1. A horizontal load was applied using a pulley weight system, and the displacement at the top of the pile was measured with a laser displacement meter, resulting in a horizontal load-displacement curve. The results indicated that the pile foundation remained in an elastic state until a displacement of 2.5 mm. Measurements of the horizontal displacement and bending moment of the pile revealed that the model pile behaves as a flexible pile; the bending moment initially increases along the pile length and then decreases, approaching zero at the pile's bottom. The vertical load test analyzed the relationship between vertical load and settlement of the single pile, as well as its variation patterns. This study provides an experimental basis for the design of single pile foundations in weathered granite formations on the southeast coast of Fujian Province and aids in optimizing offshore wind power engineering practices.

Effects of Inflow Turbulent Coherent Structures on a Small-Scale Wind Turbine in the Atmospheric Boundary Layer of Long Corridor Terrains: An Example Study in the Hexi Corridor

Considering its Venturi effect, long corridor terrain is considered as one of the outstanding wind-energy resources, but has not been developed due to unclear inflow turbulence effects on wind turbines. To advance the wind-power technology in long corridors and reveal the physics behind it, we conducted a series of data-fusion analyses combining field measurements in the Hexi Corridor, Gansu, China, and numerical simulations and summarize the effort here. In this study, the classical spectrum for the atmospheric boundary layer for wind-energy research, the IEC Kaimal spectrum (also known as IECKwind, International Elector technical Commission 61400-1) cannot describe the wind profile in corridors. Here, we proposed a new spectrum to describe the wind in the Hexi Corridor by modifying the IEC Kaimal spectrum, and we call it the IECK-HX spectrum. The results demonstrate that it preferentially resides at lower frequencies (larger spatial scales) compared with IECKwind. Large-scale motions (LSMs) and very large-scale motions (VLSMs) coexist in the Hexi Corridor atmospheric boundary layer, which can be well described by the IECK-HX spectrum, and these two dominate the large fluctuations in the power, thrust, and blade root flapwise moment of wind turbines, while the high-frequency small-scale coherent structures mainly cause high-frequency fluctuations in wind-turbine load. Furthermore, IEC Kaimal spectrum can not describe the VLSMs, and the generated flow presents significant fluctuations and thereby reduces the power output in high wind-speed regions. This study provides fundamental support for wind-energy scientists and engineers who are interested in wind energy in corridor terrains. Published by the American Physical Society 2024

Offshore Wind Power: Progress of the Edge Tool, Which Can Promote Sustainable Energy Development

Offshore wind is renewable, clean, and widely distributed. Therefore, the utilization of offshore wind power can potentially satisfy the increasing energy demand and circumvent the dependence on fossil energy. Thus, offshore wind power is an edge tool for achieving sustainable energy development because of its potential in large-scale energy supply and its important role in reducing environmental pollution as well as carbon emission brought by fossil energy. The worldwide development of offshore wind power has entered the era of large-scale research and commercial application. It displays a trend of rapid development, continuous technological breakthroughs, and high-speed market growth. This article systematically introduces the structural components and technical characteristics of offshore wind power. Moreover, the current developmental status of offshore wind power is summarized. By reviewing the current development and application status of offshore wind power technology worldwide, large wind turbines and fixed and floating offshore wind power technologies are analyzed. Additionally, the development of the offshore wind energy market is overviewed. The policy condition and key aspects such as the construction, operation, and maintenance of offshore wind power plants are also summarized. Finally, the prospective challenges and development trends of offshore wind power and its significance in achieving sustainable society development are proposed. We consider that the article can provide reference and inspiration for researchers and developers dedicated to offshore wind power.

Structural Design and Research of Offshore Wind Turbine Towers

The structural design and research of offshore wind turbine tower need to involve knowledge and technology in many fields, such as mechanical engineering, material science, fluid mechanics and so on. Through the research and optimization of tower structure, it can promote the development of related industries and improve the technical level and competitiveness of the whole industrial chain. The structural design and research of offshore wind turbine tower has important practical significance and application value. Through in-depth research and optimization of design, the performance and reliability of offshore wind turbines can be improved, and the rapid development of offshore wind power technology can be promoted.

Experimental Study on Aerodynamic Characteristics of Downwind Bionic Tower Wind Turbine.

The vibrissae of harbor seals exhibit a distinct three-dimensional structure compared to circular cylinders, resulting in a wave-shaped configuration that effectively reduces drag and suppresses vortex shedding in the wake. However, this unique cylinder design has not yet been applied to wind power technologies. Therefore, this study applies this concept to the design of downwind wind turbines and employs wind tunnel testing to compare the wake flow characteristics of a single-cylinder model while also investigating the output power and wake performance of the model wind turbine. Herein, we demonstrate that in the single-cylinder test, the bionic case shows reduced turbulence intensity in its wake compared to that observed with the circular cylinder case. The difference in the energy distribution in the frequency domain behind the cylinder was mainly manifested in the near-wake region. Moreover, our findings indicate that differences in power coefficient are predominantly noticeable with high tip speed ratios. Furthermore, as output power increases, this bionic cylindrical structure induces greater velocity deficit and higher turbulence intensity behind the rotor. These results provide valuable insights for optimizing aerodynamic designs of wind turbines towards achieving enhanced efficiency for converting wind energy.

Pembuatan Prototype Pengereman Turbin Pada Pembangkit Listrik Tenaga Bayu Dengan Menggunakan Dummy Load Resistor

This study aims to develop a prototype braking system for wind turbines used in wind power plants by utilizing a dummy load resistor. The background of this research is the necessity for an effective braking system to control the speed of wind turbines, especially under extreme wind conditions, which can cause damage to the system and electrical components. The designed braking system uses a dummy load resistor to reduce the rotational speed of the turbine by dissipating excess electrical energy as heat. Tests were conducted to evaluate the effectiveness of the system under various wind conditions and to measure performance parameters such as turbine speed stability and protection of electrical components. The results show that the uses of dummy load resistors are effective in diverting excess voltage with a set point of 14 volts, and at 300 rpm using voltage sensors, proximity sensor and MOSFETs as voltage control, which will be diverted to the dummy load resistor system. Thus, this research makes a significant contribution to the development of wind power technology, particularly in terms of safety and operational efficiency.

Wind-Induced Response Analysis and Fatigue Life Prediction of a Hybrid Wind Turbine Tower Combining an Upper Steel Tube with a Lower Steel Truss

Based on the WindPACT-3MW wind turbine tower commonly used in wind power engineering, a finite element model (FEM) of a hybrid wind turbine tower combining an upper steel tube with a lower steel truss is designed and established. On this basis, a static optimization analysis, wind-induced vibration analysis, and fatigue life analysis of the hybrid tower structure are performed. The results show that under the same design parameters, the overall stiffness and static bearing capacity of the tower structure can be significantly improved by using subdivided truss webs, increasing the truss height as much as possible and increasing the width of the truss base appropriately. Under normal operation conditions, the response of the tower structure in the along-wind direction is significantly greater than the response in the crosswind direction, indicating that the aerodynamic thrust generated by the rotation of the blades is the main factor causing the wind-induced vibration of the tower structure. For the tower structure analyzed in this study, when considering the entire range of wind speeds from the cut-in wind speed to the cut-out wind speed, the fatigue life of the structure is 38.5 years.

Anomaly detection in wind turbine blades based on PCA and convolutional kernel transform models: employing multivariate SCADA time series analysis

With the widespread application of wind power technology, the detection of abnormalities in wind turbine blades has become a key research area. The use of data from monitoring and data acquisition (SCADA) systems for data-driven fault detection research presents new challenges. This study utilizes short-term SCADA data from wind turbine generators to classify the blade abnormal and normal operational states, thereby introducing a new method called PCABSMMR. This strategy integrates principal component analysis (PCA) and borderline-synthetic minority over-sampling technique (Borderline-SMOTE) for data processing and utilizes an improved multi-dimensional time series classification (MTSC) model. It combines one-dimensional convolution from deep learning with shallow learning’s rigid classifiers. PCA is used for dimensionality reduction, while Borderline-SMOTE expands the samples of minority class fault instances. Comparative analysis with various methods shows that the proposed method has an average F1-score of 0.98, outperforming many state-of-the-art MTSC models across various evaluation metrics.

Adaptive event-triggering mechanism based Takagi-Sugeno fuzzy automatic generation controller design for offshore wind power system

Interconnected offshore wind power system (OWPS) attracts widespread attention due to its special advantage. With the development of wind power technology, higher requirements are put forward for the reliability of networked OWPS. Considering the nonlinear characteristics of OWPS and limited network bandwidth resource, an adaptive multi-event triggering mechanism based distributed Takagi-Sugeno fuzzy robust H∞ control scheme is investigated in this paper. A modeling method for OWPS integrating communication constraints is proposed. By Lyapunov stability theory, the sufficient condition for the asymptotical stability of OWPS has been derived. Compared with traditional control scheme, the proposed Takagi-Sugeno fuzzy controller provides smoother output power, smaller torque oscillation and higher wind energy utilization. Furthermore, the co-design strategy increases the utilization rate of network bandwidth. The feasibility of adaptive multi-event triggering mechanism based Takagi-Sugeno fuzzy controller is demonstrated through a simulation example.

Multi-dimensional low-carbon assessments of wind-driven seawater desalination system via hybrid life cycle modeling

Wind-driven desalination is a representative technology of renewable energy that not only alleviates water shortages but also reduces greenhouse gas (GHG) emissions generated by the utilization of fossil fuels. This study examined the GHG emissions from a wind-driven seawater desalination system by using the hybrid input-output life-cycle analysis (IO-LCA) to undertake a comprehensive low-carbon assessment by comparing with traditional thermal seawater desalination systems over the whole life cycle. The findings indicate that the GHG emissions of the wind-driven seawater desalination system are 96.14% lower than those of the traditional system. According to estimations, if reverse osmosis (RO) desalination is driven by wind power technologies at a larger scale, the annual GHG emissions can be reduced by an amount between 7.54E+05 and 3.71E+06 t CO2-eq. Although the construction stage increases the emissions to 55.41% over the whole life cycle, the payback period (Ypp) is about 2.69 years, which means that the level of GHG emissions could be reduced by 25.42% of the level of the traditional systems. Based on the multi-dimensional low-carbon assessment, this study is expected to provide quantitative assessments and policy implications to integrate low-carbon technologies with seawater desalination and promote sustainable development of seawater desalination industries.

Causal Analysis of Accidents During Wind Power Engineering Construction Using Bayesian Networks

Causal Analysis of Accidents During Wind Power Engineering Construction Using Bayesian Networks

Teaching practice of wind turbine practical training based on virtual teaching platform

AbstractThe wind turbine components are bulky and costly. Undergraduate students majoring in wind power cannot achieve professional skills training in the laboratory. To deepen the understanding of wind turbine installation, a virtual simulation platform for the teaching exploration of wind turbine assembly practice course is developed. The goal of the platform is to build a virtual simulation installation process of each huge component of the wind turbine through the model, so that students can experience the experiential learning of the installation of the wind turbine, and experience the learning opportunities of the visualization of parts and the operability of the assembly process, so as to lay the foundation of wind power engineering practice for undergraduate students. The teaching of simulation working process based on wind turbine assembly process and performance characteristics is discussed. The results and questionnaires of students in three classes are counted. The teaching experiment shows that the average score of the experimental group is 4.5 points higher than that of the control group. This method can significantly improve students' interest in learning and academic performance, improve students' wind turbine assembly ability, and meet the actual needs of students majoring in wind power. The research shows that the platform can be effectively used as a practical teaching tool for wind power students.

Optimization and control strategy for wind turbine aerodynamic performance under uncertainties

Aerodynamic performance of wind turbine governs the overall energy efficiency, which has been an ever-lasting research focus in the field of wind power technology. Due to the coupling effect among the highly complex environmental and structural uncertainties, the practical aerodynamic performance may not be reliably predicted. To aggravate, this performance declines with time in service. It is of great significance to efficiently and reliably assess the impact of uncertain factors and reduce these influences on wind turbine aerodynamic performance. This paper establishes an uncertainty analysis and robustness optimization model of wind turbine aerodynamic performance considering wind speed and pitch angle error uncertainties. An approach combined the no-instrusive probabilistic collocation method is used, and the blade element momentum theory is applied to quantify influences of variable uncertainties on NREL 5 MW wind turbine aerodynamic performance. The optimization target is to reduce the sensitivity of wind turbine aerodynamic performance to uncertainties, as well as maintain capture power. The results show that the wind turbine aerodynamic and mechanical performance will be greatly affected with uncertain factors. By optimizing and adjusting wind turbine rotor speed and blade pitch angle, the wind turbine rotor power and thrust load variation can be reduced to 9.14% and 9.36%, respectively, which indeed reduces the uncertainty effects.

Public support and opposition toward floating offshore wind power development in Norway

For countries like Norway, with abundant offshore wind resources and deep seas, floating wind power technology can play an essential role in the green energy transition. However, this technology is still immature, and the first utility-scale floating offshore wind power projects need substantial support for technology development to be commercially feasible. This study employs an online survey targeting the general population in Norway (N = 1011) to investigate support and opposition toward floating offshore wind power development. The survey includes a discrete choice experiment focusing on policy-relevant factors such as the export of electricity, reducing domestic carbon emissions by electrifying offshore oil and gas platforms, impact on global technology cost trends, and involving domestic offshore industries as key players in the floating offshore wind sector. We find the highest support for developing projects that utilize technology from domestic offshore industries and projects connected to the domestic electricity grid. Projects aimed at reducing domestic carbon emissions by electrifying offshore oil and gas platforms are favored over those for exporting electricity to other countries. A significant impact on future technology costs does not lead to increased support for the project. Projects presented after a framing text focusing on meeting future electricity demand result in a higher willingness to pay for floating offshore wind projects than those presented after a framing text focusing on meeting climate objectives. Respondents opposing all the projects are likely climate skeptics and believe that project developers should bear all the project costs. Norway is expected to play a critical role in developing floating wind power. However, the Norwegians demand clear national benefits to be willing to shoulder the cost of spearheading the floating offshore wind power development. Understanding these preferences is vital for crafting energy policies aligning with public interests and rapidly integrating floating wind power into the green energy transition.

Using Patent Data to Evaluate the Knowledge Dissemination of the Offshore Wind Power Industry

Many countries use the offshore wind power technology as renewable energy for sustainable development. In this study, we will focus on the knowledge dissemination of the offshore wind power technology. Not every country has the ability to develop their own offshore wind power technologies. The knowledge dissemination on sustainable technology could bridge the technology gap among the developer and promote the development of sustainable clean energy technology. Some objective evaluation indicators of knowledge dissemination will be carried out in this research and help to find appropriate companies to assist the local industry on offshore wind power industry. The public patent information is used to build a model to bring evaluation indicators about knowledge dissemination. These evaluation indicators include the revealed symmetric technological advantage index (RSTA), the knowledge density index ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">D_c,m,t</i> ), and the relatedness knowledge base index ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">R_c,r,t</i> ). For RSTA, <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">D</i> and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">R</i> indicators, Siemens Aktiengesellschaft, Vestas Wind Systems, Siemens Gamesa Renewable Energy, and Aloys Wobben have higher values, which can be evaluated to have the higher degree of knowledge dissemination in the field of offshore wind power technology. Unlike previous studies that only using patent bibliographic data alone, employ evaluation indicators can extract more information about the knowledge dissemination. This study presents a promising method to evaluate the degree of knowledge dissemination in offshore wind power technology by using patent data.

Review of Wind Power Bearing Wear Analysis and Intelligent Lubrication Method Research

With the significant penetration of wind generation, wind turbines require higher and higher lubrication performance for bearings. To improve the lubrication performance of wind power bearings, this study takes wind power bearings as the research object and comprehensively analyzes the wear forms of wind power bearings as well as intelligent lubrication methods. Firstly, the main roles and wear forms of wind turbine bearings are sorted out and analyzed. Secondly, the common lubrication problems of wind power bearings are analyzed from the bearing grease selection, lubrication mode, and lubrication status, highlighting the important influence of lubrication on bearings. Thirdly, the wind turbine bearing wisdom lubrication method research and organization, mainly including the wind power generation bearing lubrication materials, lubrication devices and monitoring methods, and other issues of research and analysis. Finally, current challenges and future development directions are summarized, which are designed to provide theoretical reference and technical support for the related research and engineering practice in the field of wind power engineering.

Using acoustic emission for condition monitoring of the main shaft bearings in 4-point suspension wind turbine drivetrains

ABSTRACT The continuous growth of wind power technology makes condition monitoring of wind turbine components crucially important for their operational efficiency. The main shaft bearings in wind turbines have been identified as one of the most critical components in the system, especially with the ongoing increase in rotor size and weight. This increase made the 4-point suspension drivetrain more preferable. In this study, we present a novel approach for condition monitoring of the main shaft bearings in a 2 Megawatt wind turbine with 4-point suspension drivetrain using primarily acoustic emission (AE). The focus was on the analysis of time and frequency domains of the AE signal, where the dominant frequency of each AE hit was identified and plotted back in the time domain to create the so-called dominant frequency map in specific time intervals for each bearing. A comparison between the two dominant frequency maps of the two bearings gives valuable insights into the condition of the two bearings. The distinctive nature of the dominant frequency bands in the dominant frequency maps presented promising potential for this method. The presented method is straightforward and can be automated and then integrated into a planned predictive maintenance programme for this wind turbine.

Energy Status in Africa: Challenges, Progress and Sustainable Pathways

Access to modern energy is essential for socioeconomic development, yet Africa faces significant challenges in this regard. For example, Sub-Saharan Africa (SSA) is marked by economic underdevelopment and poverty largely due to the non-environmentally friendly energy used (wood, charcoal) and limited access to modern energy resources. Indeed, this review provides an overview of the African energy landscape; it provides a comprehensive renewables-focused energy pathway for developing a cleaner and more sustainable African energy system. It explores end-use sector electrification in both rural and urban areas in Africa. It emphasizes the rapid expansion of renewable generation, the challenges facing and solutions for the implementation of renewable energy, and the role of emerging technologies. It also presents technological pathways and investment opportunities that will enrich the regional debate and help accelerate the energy transformation across Africa. The analysis demonstrated that the current trends of renewable energy used are hydropower, wind power, biomass, and geothermal energy. The electrification rate in West Africa is less than 58% in urban areas and less than 25% in rural areas. Results show that 65% of the SSA population does not have access to electricity and 81% rely on wood and charcoal. In West Africa, only Ghana (70% or so) and Cape Verde (95.9% or so) have equitable access to electricity between rural and urban areas. The potentiality of solar irradiance in Africa ranges between 3 and 7 KWh/m2/day. The wind speed ranges from 3 m/s to 10 m/s; the wave power can range from 7 to 25 kW/m per site in island regions. Egypt, Morocco, Ethiopia, Tunisia, and South Africa are, respectively, countries leading in wind power technology, and solar energy technology was more advanced in North Africa and South Africa. Finally, geothermal is only developed in Kenya and Tanzania and Kenya is the leader in that field. Although renewable energy in Africa is still growing year to year, it still faces power outages because most renewable energy potentialities are not yet exploited, the technologies used are weak, there is insufficient funding, there is ineffective infrastructure, and there are inadequate or no policies in that field.

Evaluating rare-earth constraints on wind power development under China's carbon-neutral target

China proposed a target to achieve carbon neutrality before 2060. Wind power is crucial for mitigating climate change and achieving carbon neutrality. However, its development depends on the potential constraints of rare-earth elements. Therefore, first projecting the rare-earth demand for wind power equipment in the context of achieving carbon neutrality and identifying potential obstacles are necessary. However, the carbon-neutral pathway for China's power sector is unclear, let alone the corresponding rare-earth demand. Consequently, this study explores a potential cost-effective carbon-neutral pathway for China's power sector and quantifies the demand for rare-earth elements used for producing wind power equipment under different pathways, by integrating dynamic material flow analysis and a national energy technology model. The results showed that the rare-earth supply may be inadequate for wind power development in terms of achieving carbon neutrality in China, especially for dysprosium and terbium. To neutralise the carbon emissions of China's power sector, the cumulative rare-earth demand during 2021–2060 would be 222–434 kt, of which at most 1/3 could potentially be obtained by circular usage from end-of-life wind turbines. However, the existing low secondary recovery rate of rare-earth elements makes the available circular amounts very small. Shifting to a wind power market dominated by direct-drive turbines may increase the cumulative rare-earth demand by up to 34 %. Without material intensity reduction for the wind power technologies, an additional 38 % demand for rare-earth elements will occur, exacerbating the risk of shortage.