Civil Engineering Reference
In-Depth Information
FIGURE 5-12
Optimum tower spacing in wind farms in flat terrain.
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larger turbines cost less per MW capacity and occupy less land area.
•
fewer large machines can reduce the MWh energy crop per year,
as downtime of one machine would have larger impact on the
energy output.
•
the wind power fluctuations and electrical transients on fewer large
machines would cost more in electrical filtering of the power and
voltage fluctuations, or would degrade the quality of power, invit-
ing penalty from the grid.
takes into account the above
trades. Additionally, it includes the effect of tower height that goes with the
turbine diameter, the available standard ratings, cost at the time of procure-
ment, and the wind speed. The wake interaction and tower shadow are
ignored for simplicity.
Such optimization leads to a site specific number and size of the wind
turbines that will minimize the energy cost.
The optimization method presented by Roy
2
5.6
Maximum Power Operation
As seen earlier, operating the wind turbine at a constant tip-speed ratio
corresponding to the maximum power point at all times can generate 20 to
30 percent more electricity per year. However, this requires a control scheme
