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...

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...

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...

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. ...

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...

Nowadays, power systems, energy generation by wind has been very important. Noting that the production of electrical energy by wind turbines on site 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, several different types of turbines in the market the...

Due to the wind speed variation, wind shear and tower shadow effects, grid connected wind turbines are the sources of power fluctuations which may produce flicker during continuous operation. This paper presents a model of an MW-level variable speed wind turbine with a doubly fed induction generatorto investigate the flicker emission and mitigation issues. An individual pitch control (IPC) stra...

Wind-profiling lidars are now regularly used in boundary-layer meteorology and in applications such as wind energy and air quality. Lidar wind profilers exploit the Doppler shift of laser light backscattered from particulates carried by the wind to measure a line-of-sight (LOS) velocity. The Doppler beam swinging (DBS) technique, used by many commercial systems, considers measurements of this L...

Existing fossil fuels do not meet the needs of modern societies and are almost coming to an end. Hence, governments can respond both to the needs of the people and the industry, by investing in the use of renewable energies. As well as saving fossil fuels, natural gas and even water. According to the research, renewable energy, especially wind energy, has been used in recent years and are able ...

With the growing demand for cost-effective wind energy, optimization of wind turbine components has been gaining increasing attention for its acknowledged contributions made to design enhancement, especially in early stages of product development. One of the major design goals is the accurate determination of structural dynamics and control, which is di‐ rectly related to fatigue life and cost ...