نتایج جستجو برای: wind power density

تعداد نتایج: 929494  

2014
Xu Wang Bin Chen Dezhang Sun Yinqiang Wu

Through the wind velocity and direction monitoring system installed on Jiubao Bridge of Qiantang River, Hangzhou city, Zhejiang province, China, a full range of wind velocity and direction data was collected during typhoon HAIKUI in 2012. Based on these data, it was found that, at higher observed elevation, turbulence intensity is lower, and the variation tendency of longitudinal and lateral tu...

2003
W. Steffen

By way of axisymmetric numerical hydrodynamical simulations we study the interaction of a fast tenuous stellar wind with a thick toroidal distribution of high-density clouds embedded in a stationary intercloud medium with a power-law density fall-off of index −1.9. We find that the supersonic wind percolates through the cloud ensemble, producing finger-like structures in the contact discontinui...

2010
W. Timothy Liu Wenqing Tang Xiaosu Xie

With the increasing demand of electric power and the need of reducing greenhouse gas emission, the importance of turning wind energy at sea into electric power has never been more evident. For example, China is vigorously studying and pursuing the potential of wind energy to lessen dependence of coal consumption (McElroy et al., 2009). The White Paper on Energy (DTI, 2007) lays out an ambitious...

صالحی دوبخشری, احمد , فتوحی فیروزآباد, محمود ,

The increase in fossil fuel prices has resulted in growing utilization of renewable energy sources in power systems. Wind energy as an economical source of energy has experienced the fastest growth among other energy sources. Traditionally, renewable energy sources as a result of their random nature have not been considered in the process of generation expansion planning. The increase in fossil...

2009
Shuguang Li

We study a parallelized flapping piezo-leaf generator for harvesting ambient wind energy and demonstrate an initial design. We fabricated prototypes in various configurations and performed a series of experiments to study performance trends. We propose a novel vertical-stalk L-shape design that exhibits improved output power density over horizontal piezoelectric configurations. While a signific...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه شهید بهشتی - دانشکده علوم زمین 1388

چکیده ندارد.

This paper presents modeling, simulation and control of matrix converter (MC) for variable speed wind turbine (VSWT) system including permanent magnet synchronous generator (PMSG). At a given wind velocity, the power available from a wind turbine is a function of its shaft speed. In order to track maximum power, the MC adjusts the PMSG shaft speed.The proposed control system allowing independen...

Due to incremental use of renewable energies, some challenges have been arised in control of wind power systems. One of the important ones is the uncertainty of wind power that affects directly on the cost of utilization. In this paper some algorithms based on the fuzzy logic and neural networks have been implemented to analyze the uncertainty of the wind power using historical data collected f...

2013
Jen-Hao Teng Rong-Ceng Leou

The harmonic impact caused by wind turbines should be carefully investigated before wind turbines are interconnected. However, the harmonic currents of wind turbines are not easily predicted due to the variations of wind speed. If the harmonic current outputs can be predicted accurately, the harmonic impact of wind turbines and wind farms for power grids can be analyzed efficiently. Therefore, ...

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