Page 358 - Fluid Power Engineering
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318 Chapter Fourteen
Collection System and Substation Construction
This section pertains to construction and installation of the electrical
infrastructure. A crew that specializes in electrical systems performs
does these tasks.
Collection system. Most projects use underground power and
communications cables from the turbines to the substation.
Trenches are dug 4–6 ft deep and 1 ft wide. Power cables are
placed first and backfilled with soil that has acceptable ther-
mal resistivity. The communications cables are placed over
the power cables with several inches of backfill in the middle.
Specialized trucks are used for laying cables. If the backfill
soil does not have acceptable conduction properties to move
the heat, then the conductors can fail leading to expensive re-
pairs. Therefore, heat conductivity of soil must be tested and if
backfill soil is inappropriate, then alternate backfill material is
used. In addition, the cables must be inspected to ensure there
is no pinching of cables before the trenches are compacted.
Substation and maintenance building construction. Substation
normally contains pad-mounted transformer, metal-enclosed
switchgear, and other components like capacitors, if neces-
sary. In any electrical installation, the following are key to
safe operations: Proper grounding; testing of relay settings;
tight connections between conductors and equipment.
SCADA Systems. Installation and testing of SCADA system is
done before commissioning can start. This involves installa-
tion of all the telecommunications equipment, SCADA server,
SCADA software, and configuration. Testing of the SCADA
system involves testing if each device that is connected to the
SCADA system is able to:
Transmit status data when requested
Store operating data received from a device
Control of wind turbines based on stored logic
Communicate with external systems like grid operator, tur-
bine manufacturer, and others
Provide remote access
Generate reports
Commissioning
Commissioning of a wind farm is usually an elaborate handover pro-
cess of the project from the contractor and turbine manufacturer to
the project owner. The following entities are usually involved:
