Page 219 - Fluid Power Engineering

190 Chapter Nine

The design assessment verifies that all the design cases, load
assumptions, and safety factors used in design of all the
major components, blades, drive train, and tower meet the
established standard. It also verifies the controls, protec-
tion systems and electrical components, manufacturing plan,
installation plan, operations and maintenance plan, and per-
sonnel safety plan. In addition, a review of documentation
pertaining to the turbine operations, commissioning, and
maintenance is performed.
Type Testing Conformity Statement. In this module, the turbine

is functionally tested and the design loads on key components
are verified through measurement in a realistic test environ-
ment. NREL’s National Wind Turbine Center (NWTC) is one
of the centers in the United States that provides type testing
services. In addition to safety, functional tests, and verifica-
tion of performance curves the following are also performed:
Dynamic and static blade tests and load measurements of
other key components under a variety of loading scenarios—
different wind speeds, different turbulence, startup, normal
shutdown, emergency shutdown, variety of failure modes,
and others.
Manufacturing Conformity Statement. In this module, the man-

ufactured turbine and the manufacturing processes are eval-
uated to ensure that (a) the manufacturing processes conform
to the specifications in the design document about how com-
ponents should be made, (b) all the other associated processes
like procurement and quality assurance are adequate to en-
sure quality in manufacturing. ISO 9001 accreditation of the
manufacturing processes, although not required, takes care of
most of the requirements.
Type Characteristics Measurements (optional). In this module,

measurements are performed to validate the power produc-
tion curve, power quality parameters, and noise emissions of
the turbine.

In the Design Evaluation Conformity Statement module of the cer-
tification process, the assumptions, inputs, and results of the aeroe-
lasticity analysis are submitted to certification agency for verification.
The certifying agency or the design evaluation agency verifies the
calculations in some cases repeats the calculations with a different
software package.
After the conduct of the above evaluations, if the turbine complies
with the standards, then a verification report and type certificate is
issued by the certification entity.