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renewable
energy
saved to a single server, but there are
considerably more critical machines
to look after than for a typical power
station. The complexity of the analy-
sis can be especially time consuming
for a WTG application. A centralised
centre for wind turbines is an impor-
tant alternative to traditional diagnos-
tic support services where faults are
both detected and diagnosed, and
recommended action is directly re-
ported to the customer service group.
This "back-office" type of diagnostics
and analysis service is especially im-
portant for a wind farm since
there is no vibration safety
monitoring done to pro-
tect the WTGs. As the
diagnostics are done
remotely at the Sur-
veillance centre,
there is no need for
a local diagnostic
server or database
for the customer's
IT department to take
care of.
Compliance
There are several standards that
govern steam turbine monitorings,
but not so for wind turbines.
Germancher Lloyd is the current de
facto certifying body for condition
monitoring systems on WTGs. The
insurance company Allianz has also
taken a keen interest in how these
assets are monitored from an insur-
er's point of view.
Conclusion
Wind turbine monitoring requires a
system that is specifically dedicated
to wind turbines.
You can find out more about Brüel &
Kjær Vibro's Wind Turbine Monitoring
System (Type 3652) on our website
www.bkvibro.com.
n
comprehensive monitor-
ing strategy with specialized
measurement techniques to
ensure a wide range of poten-
tial failure modes can be de-
tected. Monitoring to alarm lim-
its is a necessity, but in a WTG
application, there can be many
alarms that occur under such
conditions. Therefore an intelli-
gent Alarm management system
is needed to suggest the severity of
the alarms so the system operator is
not "drowning in blinking lights".
Machines and Operating
Conditions
Steam turbines are operating at
steady load for long periods of time,
with little change in operating condi-
tions.
WTGs operate within a wide range
of operating conditions. Vibration
and process parameter amplitude
values vary not only due to devel-
oping faults, but also to operating
conditions. In order to detect faults
early and to accurately trend them,
these two phenomena have to be
de-coupled. This is done using what
is called an
adaptive monitoring strategy. This
strategy is important for all types
of machines, including steam tur-
bines, but it is especially important
for WTGs.
Monitoring and Diagnostics
Support
A steam turbine power plant may
have four or so generating units,
each consisting of a single genera-
tor, several turbine stages, and a
number of auxiliary machines such
as pumps, fans and motors. All data
can be trended and analyzed from a
single server.
A wind farm can consist of up to 30
or more wind turbines, each consist-
ing of the main bearing, gearbox and
generator. All of this data can also be
Figure 1. Typical rack-based system
in the back, for thermal power plants
(COMPASS). The laptop sized sys-
tem in front is dedicated to wind tur-
bines (3652).