Twenty six sequences of optically thick wind solutions have calculated which mimic time-dependent evolution of classical novae of populations I and II. The peak of the new opacity around log T = 5:2 due to iron lines is found to be strong enough to accelerate the winds even in very low iron abundance such as Z=0.001 for massive white dwarfs ( 0:8M ). The old population novae show the slow light...

As the wind power generation develops, the Doubly Fed Induction Generator (DFIG) based wind power system may suffer Sub Synchronous Resonance (SSR) and High Frequency Resonance (HFR) in the series and parallel compensated weak network. The principle and frequency of HFR have been discussed using the Bode diagram as an analysis tool. However, the HFR can be categorized into two different types: ...

The flux footprint probability distribution (FPD) for the near-surface receptor over a series of sinusoidal hills is evaluated using a backward Lagrangian stochastic (LS) model. The wind and turbulence fields derived from large-eddy simulations under unstable conditions, in which the synoptic wind aligns with the surface-elevation-varying direction, are used to drive the LS model. The character...

As Wind Power Penetration increases continuously in total Power Generation, the wind turbines are necessary to stay connected to grid even under grid disturbances. An enhanced control strategy for DFIG is proposed in the present paper to meet the latest grid codes set by grid operators. The Decoupled Current Controller implemented in Grid Voltage oriented reference frame is applied to Grid Side...

Although most of the planetary boundary layer (PBL) parameterizations have demonstrated the capability to reproduce many meteorological phenomena in the lowest few kilometers, little attention has been paid to the prediction of the diurnal cycles of surface wind speed (VSFC) in relation to surface temperature (TSFC). In this study, the performance of five widely used PBL parameterizations in re...

Spatial Genetic Structure (SGS) is correlated with life history traits and is affected by ecological and demographic processes. We discuss here the SGS within populations of three species from Cerrado Biome, Caryocar brasiliense, Dipteryx alata and Tibouchina papyrus, which vary in life history traits. Our working hypothesis was that self-incompatible and wind-dispersed species present no SGS d...

wind power generation is variable and uncertain. in the power systems with high penetration of wind power, determination of equivalent operating reserve is the main concern of systems operator. in this paper, a model is proposed to determine operating reserves in simultaneous market clearing of energy and reserve by stochastic programming based on scenarios generated via monte carlo simulation ...

Wind power development is booming globally, and large scale onshore wind power is under development in China, the Americas and India. Compared with AC transmission, HVDC technology can due to lower losses be attractive if the distance from generation to consumption is long. VSC (Voltage Source Converter) HVDC is rapidly maturing as a technology, and offers some significant advantages compared t...

A number of environmental factors control both tropical cyclogenesis and tropical cyclone (TC) intensity, contributing to the challenge of TC prediction. Among these environmental controls is the interaction of TCs with environmental vertical wind shear. Since environmental vertical wind shear is always present in varying amounts during the life of any TC, it is important to understand how wind...