Page 254 - Fluid Power Engineering

CHAPTER11

Deploying Wind

Turbines in Grid

We speak of electrical energy as “current”: it exists only while it runs
away; we use it only by delaying its escape.
—Wendell Berry, “The Use of Energy,”
The Unsettling of America, 1977

Introduction
In this chapter, the focus is on the interactions between the grid and
a wind farm. The first section discusses how the variability of wind
energy is handled on the grid and how wind energy is integrated into
the grid. The next section is an introduction to the various electrical
components that are between the turbine and the grid, followed by
introduction to transmission and distribution, and conductors that
carry current in a wind farm. The standards for interconnection are
discussed next. This is followed by description of alternate wind farm
topologies.
Electrical protection systems that protect the various elements of a
wind farm, along with lightning protection, is described in this chap-
ter. This is followed by interconnection studies conducted by utili-
ties in the United States to approve a project. The final section of the
chapter is about Supervisory control and data acquisition (SCADA)
systems for data collection, monitoring, and control.

What Happens on a Grid When There Is No Wind?
Despite all the advantages of wind energy, there is a serious disadvan-
tage: Variability of the wind resource, the raw material. When wind
speeds are low, there is no or low energy production. This section will

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