This paper presents a control strategy for wind turbines to enhance their fault ride-through capability. The controller design is based on pitch controlled variable speed wind turbine equipped with doubly-fed induction generator (DFIG). The fault ride-through is realized by injecting a crowbar with variable resistance on the generator rotor circuit. To reduce the mechanical loads induced by gri...

Knowledge of the mesoscale wind systems is very important to understand the dispersion of pollutants, thermal regulation and human comfort in the city. Wind field modifications brought about by the growth of the city of Lisbon and the possible urban environmental impacts are presented. In the last years the city of Lisbon has been growing towards the northern districts and the city center loose...

An example of sensor synergy of active and passive microwave instruments for observations of marine surface winds is demonstrated using data from the Advanced Earth Observing Satellite-II (ADEOS-II), which carried a Ku-band microwave scatterometer, SeaWinds, and the Advanced Microwave Scanning Radiometer (AMSR). Scalar wind speed observed by AMSR was evaluated by using wind speed observed by Se...

Hydrodynamic models are used to analyse water networks (water distribution, drainage, surface water, district heating, etc.). The non-linear nature of flows necessitates the use iterative solution methods in hydraulic modelling. This requires a relatively large computational effort. To reduce this effort, networks, network forcing and/or flow often simplified and analysed using Graph Theory. si...

Modern utility-scale wind turbines are typically controlled using yaw, generator torque, and blade pitch actuation (Pao and Johnson, 2011). The yaw motor is used to align the rotor with the wind direction for the purpose of maximizing power capture. Generator torque is controlled during below-rated (region 2) operation to maximize power capture by maintaining the optimal tip speed ratio. In abo...

LIDAR systems are able to provide preview information of wind speed, direction and shears at various distances in front of the wind turbines. This technology paves the way for new control concepts such as feedforward control and model predictive control to increase the energy production and to reduce loads of wind turbines. This paper describes how the necessary information can be obtained from...

the direction and speed of winds play an important role in the occurrence of pollutions and dust stormas well as location placement for the establishment of industries and the expansion of cities. yazd is a dry area of iran, and constantly exposed to the dust particles in the air; and this in terms of human life and health issues are of special importance. in this paper a day when due to the am...

Influence of distributed generation systems in the distribution systems can increase the level of short-circuit current. The effectiveness of distributed generation systems is affected by the size, location, type of distributed generation systems technology, and the methods of connecting to distribution systems. Wind turbine system is the examples of distributed generation source. Not only does...

Atmospheric carbonyls were measured at a semi-urban site in Orléans, France, from October 2010 to July 2011. Formaldehyde, acetaldehyde and acetone were found to be the most abundant carbonyls, with average concentrations of 3.1, 1.0, 2.0 ppb, respectively in summer, 2.3, 0.7, 2.2 ppb, respectively in autumn, 2.2, 1.0, 2.1 ppb, respectively in spring, and 1.5, 0.7, 1.1 ppb, respectively in wint...

in recent years, there has been a fast growth in wind energy conversion system (wecs). there are two general types of wind turbines in wecs: fixed speed wind turbines and varying speed wind turbines.permanent magnet synchronous generator (pmsg) is one of the most attractive generators for the varying speed turbine wecs.in this paper, a fuzzy controller is proposed to control the current source ...