Conference Paper

A study on smoothing effect on output fluctuation of distributed wind power generation

Central Res. Inst. of Electr. Power Ind., Yokosuka, Japan
DOI: 10.1109/TDC.2002.1177602 Conference: Transmission and Distribution Conference and Exhibition 2002: Asia Pacific. IEEE/PES, Volume: 2
Source: IEEE Xplore


Wind power generation in Japan has shown a marked increase in recent years. This increase has aroused growing concerns about the adverse effects of wind power generation on power system control, operation, and planning, because wind power output cannot be controlled and fluctuates much more than that of the conventional power plants. However, if wind power generators am distributed over a wide area, a "smoothing effect" an output fluctuation of distributed wind turbines could be expected because of the stochastic nature of wind. This paper examines the smoothing effect of output fluctuation of dispersed wind turbines. The remits reveal that the output of a single wind turbine fluctuates almost its rated power in ten minutes and little smoothing effect is expected in a wind farm scale (i.e., within sum kilometers) for a period of 10 minutes. On the other hand, a smoothing effect can be expected for a wider area in 100 minutes.

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    • "The scaling factor √ N applied to the dynamic part of the output is justified by the assumption of incoherent fluctuations. In fact, when fluctuations are incoherent, the ratio between the fluctuation amplitude of a wind farm and of a single turbine is √ N [17],[24]. Since wind coherence is directly reflected on the coherence of wind turbine outputs. It is however worthwhile to note that Davenport's coherence expression (10) shows that only sufficiently high frequency components are truly incoherent and therefore damped with the factor √ N. Coherence of low frequency components might be taken into account by weighting them with a factor closer to the one occurring in steady state [17]. "
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