01/09 ·
uptime
m
e
gazine 5
renewable
energy
Introduction
The operation of today's large
wind power plants require efficient
maintenance strategies to ensure
uninterrupted power production and
controlled expenses to operation and
maintenance.
Essential to this effort is the ability to
predict impending breakdowns in crit-
ical components as this enables the
operator to avoid costly breakdowns
and unscheduled interruptions of the
power production. This predictive
maintenance is enabled by condition
monitoring which is the assessment
of the "health" of a machine by analy-
sis of measured signals; typically
temperatures, vibrations or lubrica-
tion oil quality or wear debris con-
tent. This paper focuses on experi-
ences gained with vibration condition
monitoring.
The application of condition monitor-
ing techniques has for decades been
an integral part of asset management
in thermal power plants, and the
technology has in recent years in-
creasingly been adopted by the wind
power industry. The general capabili-
ties of the vibration condition moni-
toring technology are therefore well
known, but the adaptation to wind
turbines has proven challenging due
to inherent physical conditions such
as rapidly varying loads and non-rigid
machine foundations. Also since wind
parks are geographically dispersed
and often located in remote areas,
cost considerations have made it
necessary to rethink the traditional
monitoring setup with one or more
on-site diagnostic specialists into a
monitoring strategy with centralised
remote monitoring of a large popula-
tion of identical machines.
Centralised monitoring, however,
separates the diagnostic special-
ists from the turbine operators and
service managers and consequently
necessitates the implementation of
clear procedures for on-site handling
of alarms raised by the condition
monitoring centre and feed back to
the same centre regarding the results
of machine inspections or service ac-
tions performed due to alarms.
On a system level, the typical geo-
graphic separation of turbines, park
operator/owner and the diagnostic
centre calls for a multi-user web-
based access to the databases
holding the turbine alarm status and
measurement data. This enables all
stakeholders to access the data they
need.
Figure 1 summarises the setup for
centralised monitoring of wind tur-
bines described above.
Figure 1.
Information
and workflow
in centralised
condition moni-
toring of wind
turbines