An atmospheric boundary layer wind tunnel study was performed to determine the overall horizontal wind load on multi-span duo-pitch greenhouses. The results of this study are intended for the stability design of inflexible cladding system greenhouses (designated as Class A in EN 13031-1) with roof pitch angles of 23–24° and ridge heights of 7.5–8m. Both static force and fluctuating pressure mea...

ABSTRACT: We apply CFD to visualize wind flow around a row of three square-plan tall buildings closely arranged in a row. Increase in wind load on the upwind building is observed when wind blows to the row at 30. CFD results show that the interference mechanism is mainly due by strong channeling of wind flow through the building gaps. This leads to highly negative pressures on building walls fa...

Offshore wind turbine (OWT) support structures are subjected to non-proportional environmental wind and wave load patterns with respect to increases in wave height and with respect to wind and wave combined loading. Traditional approaches to estimating the ultimate capacity of offshore support structures are not ideally suited to analysis of OWTs. In this paper, the concept of incremental wind-...

The non-dispatchable nature of wind generation implies that system operation depends on wind power prediction programs that forecast wind farms production with high levels of uncertainty. This means that probabilistic power analysis tools become more and more necessary in systems with high wind penetration. Probabilistic load flow becomes especially difficult when wind generation is considered....

Approximations made in day-ahead markets can result in suboptimal or even infeasible schedules for generating units and inaccurate predictions of actual costs and wind curtailment. Here we compare different optimal models of day-ahead markets based on unit commitment (UC) formulations, especially energyvs. power-based UC; excluding or including startup and shutdown trajectories; and determinist...

The use of wind power for generating electricity has experienced an uninterrupted and accelerating growth over last few decades and this growth is likely to continue. In order to enable even greater role of wind energy in power production it is necessary to increase the size and unit power of wind turbines. As wind turbines grow in size they are subjected to extreme loads and fatigue caused by ...

Modern day power systems are divided into various areas. The transmission lines that connect an area to its neighboring area are called tie-lines sharing power between two areas. Automatic Generation Control (AGC) as the name signifies it regulates the power flow between different areas while holding the frequency constant. Frequency control as a major function of automatic generation control i...

This paper investigates a novel single stage AC–AC power conversion, as an alternative to multistage AC– DC–AC power conversion topology, for interfacing the wind energy conversion system (WECS) to a grid as a distributed load system. A comprehensive dynamic model of proposed AC–AC converter is developed to satisfy all the functions of the converter. A new time switching pattern and a control m...

Optimal load shedding (LS) design as an emergency plan is one of the main control challenges posed by emerging new uncertainties and numerous distributed generators including renewable energy sources in a modern power system. This paper presents an overview of the key issues and new challenges on optimal LS synthesis concerning the integration of wind turbine units into the power systems. Follo...

Aiming at the non-stationary and stall flutter problems of wind turbine blade caused by transient load fluctuations, the dynamic properties of wind turbine were studied, the blade was simplify to a cantilever beam in case of the action of shear deformation and cross section rotating effect were considered in this analysis, equations of the blade were established based on D'Alemberts' principle ...