资源类型

期刊论文 364

年份

2023 11

2022 12

2021 17

2020 13

2019 15

2018 19

2017 33

2016 26

2015 33

2014 17

2013 12

2012 15

2011 21

2010 27

2009 29

2008 9

2007 16

2006 5

2005 2

2004 3

展开 ︾

关键词

高速铁路 14

海上风电场 9

海上风电 5

创新 4

京沪高速铁路 3

动力特性 3

发展 3

可再生能源 3

中国高速铁路 2

优化 2

动车组 2

发展战略 2

可持续发展 2

台风 2

大跨度桥梁 2

对策 2

强台风 2

微波散射计 2

海上风机 2

展开 ︾

检索范围：

排序： 展示方式：

A novel structural modification to eliminate the early coupling between bending and torsional mode shapes in a cable stayed bridge

Nazim Abdul NARIMAN

《结构与土木工程前沿（英文）》 2017年 第11卷 第2期   页码 131-142 doi: 10.1007/s11709-016-0376-4

摘要： In this paper, a novel structural modification approach has been adopted to eliminate the early coupling between the bending and torsional mode shapes of vibrations for a cable stayed bridge model generated using ABAQUS software. Two lateral steel beams are added to the middle span of the structure. Frequency analysis is dedicated to obtain the natural frequencies of the first eight mode shapes of vibrations before and after the structural modification approach. Numerical simulations of wind excitations are conducted for the 3D model of the cable stayed bridge with duration of 30 s supporting on real data of a strong wind from the literature. Both vertical and torsional displacements are calculated at the mid span of the deck to analyze both the bending and the torsional stiffness of the system before and after the structural modification. The results of the frequency analysis after applying lateral steel beams declared a safer structure against vertical and torsional vibrations and rarely expected flutter wind speed. Furthermore, the coupling between the vertical and torsional mode shapes has been removed to larger natural frequencies magnitudes with a high factor of safety. The novel structural approach manifested great efficiency in increasing vertical and torsional stiffness of the structure.

关键词： aeroelastic instability     structural damping     flutter wind speed     bending stiffness     torsional stiffness    

HTML PDF 收藏

Time-domain and frequency-domain approaches to identification of bridge flutter derivatives

Zhengqing CHEN

《结构与土木工程前沿（英文）》 2009年 第3卷 第2期   页码 173-179 doi: 10.1007/s11709-009-0034-1

摘要： Flutter derivatives are essential for flutter analysis of long-span bridges, and they are generally identified from the vibration testing data of a sectional model suspended in a wind tunnel. Making use of the forced vibration testing data of three sectional models, namely, a thin-plate model, a nearly streamlined model, and a bluff-body model, a comparative study was made to identify the flutter derivatives of each model by using a time-domain method and a frequency-domain method. It was shown that all the flutter derivatives of the thin-plate model identified with the frequency-domain method and time-domain method, respectively, agree very well. Moreover, some of the flutter derivatives of each of the other two models identified with the two methods deviate to some extent. More precisely, the frequency-domain method usually results in smooth curves of the flutter derivatives. The formulation of time-domain method makes the identification results of flutter derivatives relatively sensitive to the signal phase lag between vibration state vector and aerodynamic forces and also prone to be disturbed by noise and nonlinearity.

关键词： long-span bridges     wind-induced vibration     flutter derivatives     forced vibration test     time-domain method     frequency-domain method    

HTML PDF 收藏

A novel method for reliability and risk evaluation of wind energy conversion systems considering windspeed correlation

Seyed Mohsen MIRYOUSEFI AVAL,Amir AHADI,Hosein HAYATI

《能源前沿（英文）》 2016年 第10卷 第1期   页码 46-56 doi: 10.1007/s11708-015-0384-4

摘要： This paper investigates an analytical approach for the reliability modeling of doubly fed induction generator (DFIG) wind turbines. At present, to the best of the authors’ knowledge, wind speed and wind turbine generator outage have not been addressed simultaneously. In this paper, a novel methodology based on the Weibull-Markov method is proposed for evaluating the probabilistic reliability of the bulk electric power systems, including DFIG wind turbines, considering wind speed and wind turbine generator outage. The proposed model is presented in terms of appropriate wind speed modeling as well as capacity outage probability table (COPT), considering component failures of the wind turbine generators. Based on the proposed method, the COPT of the wind farm has been developed and utilized on the IEEE RBTS to estimate the well-known reliability and sensitive indices. The simulation results reveal the importance of inclusion of wind turbine generator outage as well as wind speed in the reliability assessment of the wind farms. Moreover, the proposed method reduces the complexity of using analytical methods and provides an accurate reliability model for the wind turbines. Furthermore, several case studies are considered to demonstrate the effectiveness of the proposed method in practical applications.

关键词： doubly-fed induction generator (DFIG)     composite system adequacy assessment     wind speed correlation    

HTML PDF 收藏

Dynamic contribution of variable-speed wind energy conversion system in system frequency regulation

Yajvender Pal VERMA, Ashwani KUMAR

《能源前沿（英文）》 2012年 第6卷 第2期   页码 184-192 doi: 10.1007/s11708-012-0185-y

摘要： Frequency regulation in a generation mix having large wind power penetration is a critical issue, as wind units isolate from the grid during disturbances with advanced power electronics controllers and reduce equivalent system inertia. Thus, it is important that wind turbines also contribute to system frequency control. This paper examines the dynamic contribution of doubly fed induction generator (DFIG)-based wind turbine in system frequency regulation. The modified inertial support scheme is proposed which helps the DFIG to provide the short term transient active power support to the grid during transients and arrests the fall in frequency. The frequency deviation is considered by the controller to provide the inertial control. An additional reference power output is used which helps the DFIG to release kinetic energy stored in rotating masses of the turbine. The optimal speed control parameters have been used for the DFIG to increases its participation in frequency control. The simulations carried out in a two-area interconnected power system demonstrate the contribution of the DFIG in load frequency control.

关键词： doubly fed induction generator (DFIG)     load frequency control     inertial control     wind energy conversion system (WECS)    

HTML PDF 收藏

Optimal placement of wind turbines within a wind farm considering multi-directional wind speed using

A.S.O. OGUNJUYIGBE, T.R. AYODELE, O.D. BAMGBOJE

《能源前沿（英文）》 2021年 第15卷 第1期   页码 240-255 doi: 10.1007/s11708-018-0514-x

摘要： Most wind turbines within wind farms are set up to face a pre-determined wind direction. However, wind directions are intermittent in nature, leading to less electricity production capacity. This paper proposes an algorithm to solve the wind farm layout optimization problem considering multi-angular (MA) wind direction with the aim of maximizing the total power generated on wind farms and minimizing the cost of installation. A two-stage genetic algorithm (GA) equipped with complementary sampling and uniform crossover is used to evolve a MA layout that will yield optimal output regardless of the wind direction. In the first stage, the optimal wind turbine layouts for 8 different major wind directions were determined while the second stage allows each of the previously determined layouts to compete and inter-breed so as to evolve an optimal MA wind farm layout. The proposed MA wind farm layout is thereafter compared to other layouts whose turbines have focused site specific wind turbine orientation. The results reveal that the proposed wind farm layout improves wind power production capacity with minimum cost of installation compared to the layouts with site specific wind turbine layouts. This paper will find application at the planning stage of wind farm.

关键词： optimal placement     wind turbines     wind direction     genetic algorithm     wake effect    

HTML PDF 收藏

Droplet spectra and high-speed wind tunnel evaluation of air induction nozzles

Qing TANG, Liping CHEN, Ruirui ZHANG, Min XU, Gang XU, Tongchuan YI, Bin ZHANG

《农业科学与工程前沿（英文）》 2018年 第5卷 第4期   页码 442-454 doi: 10.15302/J-FASE-2017169

摘要：

A series of air induction nozzles were tested in a high-speed wind tunnel. Droplet size spectra were measured for four air induction nozzles (IDK-120-01, IDK-120-02, IDK-120-03 and IDK-120-04) each at three spray pressures (0.3, 0.4 and 0.5 MPa) and seven different air velocities (121.7, 153.4, 185.5, 218.4, 253.5, 277.5 and 305.5 km·h ). The measurement distance (0.15, 0.25 and 0.35 m) from the nozzle orifice was found to be important for the atomization of the droplets. The response surface method was used to analyze the experimental data. The results indicated that v and v of the droplets decreased quasi-linearly with increased wind speed, while v was affected by the quadratic of wind speed. v , v and v of the droplets were all proportional to the orifice size, and were not markedly influenced by the spray pressure. The percentage of the spray volume consisting of droplets with a diameter below 100 mm (%<100 mm) was found to be quadratically related to wind speed, and was not markedly influenced by the spray pressure and orifice size. However, the effect of the orifice size on the %<200 mm could not be ignored.

关键词： air induction nozzle     wind tunnel     aerial spray     droplet size spectra    

HTML PDF 收藏

大跨度桥梁抗风技术挑战与基础研究

项海帆,葛耀君

《中国工程科学》 2011年 第13卷 第9期   页码 8-21

摘要：

以我国30年大跨度桥梁的快速发展为研究背景，对3种大跨度桥梁的抗风技术挑战进行了基础性研究和应用性研究，着重探讨了悬索桥的颤振性能及其控制、斜拉桥风振性能与拉索风雨振控制、拱式桥涡激共振及其控制、特大桥梁风振精细化理论等一系列抗风关键问题。研究结果表明：悬索桥的颤振稳定性跨径上限约为1 500 m，超过甚至接近这一上限时，必须采取措施改善加劲梁的抗风稳定性；千米级大跨度斜拉桥仍具有足够高的颤振临界风速，其主要抗风问题是长拉索的风雨振动；大跨径拱桥除了个别有涡振问题之外，还没有受到结构抗风性能的影响。文章还提出了三维桥梁颤振精确分析的全模态方法、任意斜风作用下桥梁抖振频域分析方法、基于二阶矩理论和首次超越理论的桥梁颤振和抖振可靠性评价方法，揭示了桥梁颤振演化规律、驱动机理和控制原理。

关键词： 悬索桥     斜拉桥     拱桥     颤振     抖振     涡振    

HTML PDF 收藏

Evaluation of the wind energy potential of two south west sites in Nigeria

Olaleye M. AMOO

《能源前沿（英文）》 2012年 第6卷 第3期   页码 237-246 doi: 10.1007/s11708-012-0201-2

摘要： Wind resource assessment is a crucial first step in gauging the potential of a site to produce energy from wind turbines. In this paper, the wind energy potential of Abeokuta (07°03'N, 03°19'E) and Ijebu-Ode (06°47'N, 03°58'E), two south west sites in Nigeria were examined. Twenty years (1990–2010) of monthly mean wind data from a 10 m height were subjected to two-parameter Weibull analysis and other statistical analyses. The results show that the average annual mean wind speed variation for Abeokuta ranges from 2.2 to 5.0 m/s. For Ijebu-Ode, it ranges from 2.0 to 5.0 m/s. The wind power density variation based on the Weibull analysis ranges from 4.26 to 24.51 W/m for Abeokuta and from 8.54 to 76.46 W/m for Ijebu-Ode. Ijebu-Ode was found to be the better of the two sites in terms of annual variation of mean wind speed.

关键词： wind potential     wind speed     wind power density     wind gust     turbulence intensity     Nigeria    

HTML PDF 收藏

Power maximization of variable-speed variable-pitch wind turbines using passive adaptive neural fault

Hamed HABIBI, Hamed RAHIMI NOHOOJI, Ian HOWARD

《机械工程前沿（英文）》 2017年 第12卷 第3期   页码 377-388 doi: 10.1007/s11465-017-0431-4

摘要：

Power maximization has always been a practical consideration in wind turbines. The question of how to address optimal power capture, especially when the system dynamics are nonlinear and the actuators are subject to unknown faults, is significant. This paper studies the control methodology for variable-speed variable-pitch wind turbines including the effects of uncertain nonlinear dynamics, system fault uncertainties, and unknown external disturbances. The nonlinear model of the wind turbine is presented, and the problem of maximizing extracted energy is formulated by designing the optimal desired states. With the known system, a model-based nonlinear controller is designed; then, to handle uncertainties, the unknown nonlinearities of the wind turbine are estimated by utilizing radial basis function neural networks. The adaptive neural fault tolerant control is designed passively to be robust on model uncertainties, disturbances including wind speed and model noises, and completely unknown actuator faults including generator torque and pitch actuator torque. The Lyapunov direct method is employed to prove that the closed-loop system is uniformly bounded. Simulation studies are performed to verify the effectiveness of the proposed method.

关键词： wind turbine nonlinear model     maximum power tracking     passive fault tolerant control     adaptive neural control    

HTML PDF 收藏

Comparisons of bridges flutter derivatives and generalized ones

Fuyou XU , Zhe ZHANG , Cailiang HUANG , Airong CHEN ,

《结构与土木工程前沿（英文）》 2009年 第3卷 第3期   页码 272-278 doi: 10.1007/s11709-009-0042-1

摘要： The causes of the nonlinearity of self-excited aerodynamic force of bridge are interpreted from such two aspects as amplitude and wind velocity. The concept of “generalized flutter derivative” is proposed, and its physical meaning is illustrated. The graphs of the generalized flutter derivatives of plate and Sutong Bridge section model are plotted. The characteristics of all generalized flutter derivatives are compared and analyzed, and their superiorities are verified. The results indicate that the physical meaning of generalized flutter derivatives are more explicit compared to the traditional ones. It is more convenient to understand the nonlinearity properties of self-excited aerodynamic force of bridge according to the generalized flutter derivatives graphs with the wind velocity as the horizontal coordinate.

关键词： bridge     flutter derivative     generalized flutter derivative     self-excited aerodynamic force     Sutong Bridge    

HTML PDF 收藏

Condition monitoring of a wind turbine generator using a standalone wind turbine emulator

Himani,Ratna DAHIYA

《能源前沿（英文）》 2016年 第10卷 第3期   页码 286-297 doi: 10.1007/s11708-016-0419-5

摘要： The intend of this paper is to give a description of the realization of a low-cost wind turbine emulator(WTE) with open source technology from graze required for the condition monitoring to diagnose rotor and stator faults in a wind turbine generator (WTG). The WTE comprises of a 2.5 kW DC motor coupled with a 1 kW squirrel-cage induction machine. This paper provides a detailed overview of the hardware and software used along with the WTE control strategies such as MPPT and pitch control. The emulator reproduces dynamic characteristics both under step variations and arbitrary variation in the wind speed of a typical wind turbine (WT) of a wind energy conversion system (WECS). The usefulness of the setup has been benchmarked with previously verified WT test rigs made at the University of Manchester and Durham University in UK. Considering the fact that the rotor blades and electric subassemblies direct drive WTs are most susceptible to damage in practice, generator winding faults and rotor unbalance have been introduced and investigated using the terminal voltage and generated current. This wind turbine emulator (WTE) can be reconfigured or analyzed for condition monitoring without the need for real WTs.

关键词： condition monitoring (CM)     wind turbine emulator (WTE)     wind turbine generator (WTG)     maximum power point tracking (MPPT)     tip speed ratio (TSR)     rotor faults     stator faults    

HTML PDF 收藏

controller for control of active and reactive power in DFIG operating in a grid-connected variable speedwind energy conversion system

Azzouz TAMAARAT,Abdelhamid BENAKCHA

《能源前沿（英文）》 2014年 第8卷 第3期   页码 371-378 doi: 10.1007/s11708-014-0318-6

摘要： Due to several factors, wind energy becomes an essential type of electricity generation. The share of this type of energy in the network is becoming increasingly important. The objective of this work is to present the modeling and control strategy of a grid connected wind power generation scheme using a doubly fed induction generator (DFIG) driven by the rotor. This paper is to present the complete modeling and simulation of a wind turbine driven DFIG in the second mode of operating (the wind turbine pitch control is deactivated). It will introduce the vector control, which makes it possible to control independently the active and reactive power exchanged between the stator of the generator and the grid, based on vector control concept (with stator flux or voltage orientation) with classical PI controllers. Various simulation tests are conducted to observe the system behavior and evaluate the performance of the control for some optimization criteria (energy efficiency and the robustness of the control). It is also interesting to play on the quality of electric power by controlling the reactive power exchanged with the grid, which will facilitate making a local correction of power factor.

关键词： wind power     doubly fed induction generator (DFIG)     vector control     active power     reactive power     maximum power point tracking (MPPT)    

HTML PDF 收藏

DFIG sliding mode control fed by back-to-back PWM converter with DC-link voltage control for variable speedwind turbine

Youcef BEKAKRA,Djilani BEN ATTOUS

《能源前沿（英文）》 2014年 第8卷 第3期   页码 345-354 doi: 10.1007/s11708-014-0330-x

摘要： This paper proposes an indirect power control of doubly fed induction generator (DFIG) with the rotor connected to the electric grid through a back-to-back pulse width modulation (PWM) converter for variable speed wind power generation. Appropriate state space model of the DFIG is deduced. An original control strategy based on a variable structure control theory, also called sliding mode control, is applied to achieve the control of the active and reactive power exchanged between the stator of the DFIG and the grid. A proportional-integral-(PI) controller is used to keep the DC-link voltage constant for a back-to-back PWM converter. Simulations are conducted for validation of the digital controller operation using Matlab/Simulink software.

关键词： doubly fed induction generator (DFIG)     wind turbine     back-to-back pulse width modulation (PWM)     DC-link voltage     sliding mode control    

HTML PDF 收藏

Investigation of wind energy potentials in Brunei Darussalam

M. A. SALAM, M. G. YAZDANI, Q. M. RAHMAN, Dk NURUL, S. F. MEI, Syeed HASAN

《能源前沿（英文）》 2019年 第13卷 第4期   页码 731-741 doi: 10.1007/s11708-018-0528-4

摘要： Conventional power generation mainly depends on natural gas and diesel oil in Brunei Darussalam. The power utility company is now thinking of power generation using natural wind. In this paper, wind energy, being one of the most readily available renewable energy sources, was studied. The wind characteristic, velocity and directions were studied using Weibull distribution based on the measurement of wind speed at two different locations in Brunei Darussalam. These wind speed distributions were modeled using the Wind Power program. The wind rose graph was obtained for the wind direction to analyze the wind power density onshore and offshore. Based on this analysis, it has been found that the wind speed of 3 to 5 m/s has a probability of occurrence of 40%. Besides, the annual energy production at a wind speed of 5 m/s has been found to be in the range between 1000 and 1500 kWh for both the locations in Brunei Darussalam.

关键词： wind speed     Weibull distribution     wind rose     wind energy     wind power    

HTML PDF 收藏

Techno-economic evaluation of wind energy in southwest Nigeria

Muyiwa S. ADARAMOLA, Olarenwaju M. OYEWOLA, Olayinka S. OHUNAKIN, Rufus R. DINRIFO

《能源前沿（英文）》 2012年 第6卷 第4期   页码 366-378 doi: 10.1007/s11708-012-0205-y

摘要： In this study, an analysis of the wind energy potential in the southwest geo-political region of Nigeria was conducted. A 37-year (1971–2007) wind speed data set measured at 10 m height, obtained from eight meteorological stations within the region was analyzed using a 2-parameter Weibull function. Besides, a techno-economic evaluation of large wind energy conversion systems with power ratings ranging from 0.6 to 2 MW at different hub heights based on the levelized unit cost of electricity was made for the different sites considered. The result showed that electricity cost varied from 0.06997 and 0.11195 $/(kW·h) to 2.86611 and 4.58578 $/(kW·h) at limit values of turbine specific cost band intervals of 1000 and 1600 $/kW. It was further shown that Lagos, having the highest accumulated power outputs of 430.10 kW/a from DeWind D7 at 70 m hub height, is the most preferred for economically usable power generation in terms of the levelized unit cost.

关键词： mean wind speed     Weibull distributions     wind turbine     techno-economic analysis     southwest geopolitical region     Nigeria    

HTML PDF 收藏

标题 作者 时间 类型 操作

A novel structural modification to eliminate the early coupling between bending and torsional mode shapes in a cable stayed bridge

Nazim Abdul NARIMAN

期刊论文

Time-domain and frequency-domain approaches to identification of bridge flutter derivatives

Zhengqing CHEN

期刊论文

A novel method for reliability and risk evaluation of wind energy conversion systems considering windspeed correlation

Seyed Mohsen MIRYOUSEFI AVAL,Amir AHADI,Hosein HAYATI

期刊论文

Dynamic contribution of variable-speed wind energy conversion system in system frequency regulation

Yajvender Pal VERMA, Ashwani KUMAR

期刊论文

Optimal placement of wind turbines within a wind farm considering multi-directional wind speed using

A.S.O. OGUNJUYIGBE, T.R. AYODELE, O.D. BAMGBOJE

期刊论文

Droplet spectra and high-speed wind tunnel evaluation of air induction nozzles

Qing TANG, Liping CHEN, Ruirui ZHANG, Min XU, Gang XU, Tongchuan YI, Bin ZHANG

期刊论文

大跨度桥梁抗风技术挑战与基础研究

项海帆,葛耀君

期刊论文

Evaluation of the wind energy potential of two south west sites in Nigeria

Olaleye M. AMOO

期刊论文

Power maximization of variable-speed variable-pitch wind turbines using passive adaptive neural fault

Hamed HABIBI, Hamed RAHIMI NOHOOJI, Ian HOWARD

期刊论文

Comparisons of bridges flutter derivatives and generalized ones

Fuyou XU , Zhe ZHANG , Cailiang HUANG , Airong CHEN ,

期刊论文

Condition monitoring of a wind turbine generator using a standalone wind turbine emulator

Himani,Ratna DAHIYA

期刊论文

controller for control of active and reactive power in DFIG operating in a grid-connected variable speedwind energy conversion system

Azzouz TAMAARAT,Abdelhamid BENAKCHA

期刊论文

DFIG sliding mode control fed by back-to-back PWM converter with DC-link voltage control for variable speedwind turbine

Youcef BEKAKRA,Djilani BEN ATTOUS

期刊论文

Investigation of wind energy potentials in Brunei Darussalam

M. A. SALAM, M. G. YAZDANI, Q. M. RAHMAN, Dk NURUL, S. F. MEI, Syeed HASAN

期刊论文

Techno-economic evaluation of wind energy in southwest Nigeria

Muyiwa S. ADARAMOLA, Olarenwaju M. OYEWOLA, Olayinka S. OHUNAKIN, Rufus R. DINRIFO

期刊论文