نتایج جستجو برای: oscillatory wind turbine

تعداد نتایج: 114774  

Farzad Mokhtarinia Mahdi Nili-Ahmadabadi Mehdi Shirani,

The purpose of this study is to improve the aerodynamic performance of wind turbine blades, using the Ball-Spine inverse design method. The inverse design goal is to calculate a geometry corresponds to a given pressure distribution on its boundaries. By calculating the difference between the current and target pressure distributions, geometric boundaries are modified so that the pressure di...

2013
Annelies Bockstael Timothy Van Renterghem Valentine De Weirt Dick Botteldooren

This papers investigates underlying mechanisms for human response to wind turbine noise by studying the effects in terms of source detection, recognition and annoyance with and without road traffic noise. Recordings from a single 1.8-MW wind turbine have been mixed with samples of highway noise and of local roads at different signalto-noise ratios. These fragments have been presented to 50 norm...

2012
Peter Fogh Odgaard Jakob Stoustrup

This paper presents a scheme for accommodating faults in the rotor and generator speed sensors in a wind turbine. These measured values are important both for the wind turbine controller as well as the supervisory control of the wind turbine. The scheme is based on unknown input observers, which are also used to detect and isolate these faults. The scheme is tested on a known benchmark for FDI ...

2017
Marouane El Azzaoui

In recent years, wind energy has become one of the most important and promising sources of renewable energy. As a result, wind energy demands additional transmission capacity and better means of maintaining system reliability. The evolution of technology related to the wind system industry has led to the development of a generation of variable speed wind turbines that present numerous advantage...

2011
Zifeng Yang Partha Sarkar Hui Hu

An experimental study is conducted to characterize the dynamic wind loads and evolution of the turbulent vortex and flow structures in the wake of a horizontal axis wind turbine (HAWT). In addition to measuring dynamic wind loads (both aerodynamic forces and moments) acting on a wind turbine model, a high-resolution Particle Image Velocimetry (PIV) system was used to make “free-run” and phase-l...

2012
Jinkyoo Park

The stable boundary layer (SBL) is a stably stratified atmospheric layer that usually forms in the night over land when the earth cools as a result of a net loss of radiation[7]. The wind field characteristics in SBL distinctly differ from those in unstable boundary layer that forms in the daytime. Figures 1(a) and 1(b) show how the longitudinal wind speed and the wind direction change with the...

2009
N. S. Tachos

The work presented in this article aims to the calculation of the aerodynamic characteristics of the NREL phase II rotor that is a horizontal axis downwind wind turbine rotor and which is assumed to stand isolated in the space. The Reynolds averaged Navier-Stokes equations combined with the Spalart-Allmaras turbulence model that describes the three dimensional steady state flow about the wind t...

2003
Alan Mullane G. Lightbody

Abstract – This paper discusses the development of an adaptive feedback linearisation controller for a variable speed wind turbine. The controller provides an adaptive estimate of the turbine shaft torque. A feedback linearisation controller utilises the torque estimate to provide a torque reference for a field oriented squirrel cage induction machine. The induction machine is connected through...

2014
Jaehwan Lee Woojin Cho Kwan-Soo Lee

This paper presents a new method for optimizing the hub height of a wind turbine. In general, wind turbine energy production increases with the hub height, but so does the cost. Therefore, we must optimize the hub height. Here, we calculated the annual energy production using a wind probability function. This is a function of the hub height and the roughness, which is a surface characteristic. ...

2011
Saeid Nahi Seyed Mohammad Hossein Nabavi

Nowadays, power systems, energy generation by wind has been very important. Noting that the production of electrical energy by wind turbines on site is depend on to several factors (such as wind speed and profile site for the turbines, especially off the wind input speed, wind rated speed and wind output speed disconnect) is dependent. On the other hand, there are several different types of tur...

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