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Together these all form what we refer to as a ‘driveline’. However, the
VSD stands out as being quite different from the rest of its partners in
the driveline. VSDs are electronic devices and are the only ‘actors’ in
the chain with embedded intelligence. This intelligence allows for the
concept of the SOD to become a reality. The SOD concept allows these
VSDs to minimise their own downtime and also allows them to be uti-
lised as smart sensors for the entire driveline (monitoring, for instance,
motor torque temperature,main voltage, and load energy consumption).
Today, maintenance managers agree that, in most operations,
maintenance practices are 60% reactive, 30% preventive and 10%
predictive (see Figure 1). Reactive, or corrective maintenance, is a
response to an unanticipated problem or emergency. Preventive
maintenance implies the systematic inspection and detection of
potential failures before they occur. Predictive maintenance is a type
of preventive maintenance which estimates and projects equipment
condition over time, utilising probability formulas to assess downtime
risks. The SOD concept helps facilities managers and maintenance
personnel to ‘move the needle’ more in the direction of the anticipa-
tive behaviour (predictive) model.
Despite their popularity, much work still needs to be done to
fully integrate these technologies in order to develop highly
available manufacturing environments. This article explains
howVSDs can be utilised as smart devices that help tomonitor system
performance and also reveals how these devices can be converted
to function as Service-oriented Drives (SODs).
Today’s VSD phenomenon can be compared to the state of the
automobile in the 1960s. Although many families owned a car dur-
ing that era, car safety was not yet a high priority. Over the last 50
years, many automobile safety initiatives were gradually introduced
on a number of different levels. As a result of these initiatives, in
developed countries, the number of automobile-related deaths de-
creased significantly.
As with the automobile in the 1960s, even though VSDs have
reached a certainmaturity level froman installed base perspective, the
ways in which these devices are being implemented and maintained
are still immature. This is a problem because users and purchasers
of these devices are not leveraging the full energy consumption and
equipment uptime benefits of the technology.
Most VSDs are installed within a ‘chain’ of other electrome-
chanical devices (such as transformers, circuit breakers, motors) or
mechanical devices (motors, gear box, mechanical transmission).
Service-oriented Drive Deployments
Improve VSD Driveline Uptime
Philippe Hampikian, Schneider-Electric
Variable Speed Drives (VSDs) were introduced to the market several years ago, and since then, they have proliferated across many industries.
DRIVES, MOTORS + SWITCHGEAR
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