Nuclear Plant Journal, July-August 2015 NuclearPlantJournal.com
23
three-stage vertical pump into an
instrumented test loop. In parallel,
researchers developed a reduced-
order finite element analysis model
using initial testing results and
demonstrated that the model could
predict and match real sensor
responses. The instrumented test
pump allowed the team to compare
real sensor response to imposed
faults with predicted pump response
from the virtual sensor model. More
information is available in Initial
Development of Virtual Sensors for
Vertical Pumps (3002002446).
• Fault trials: In 2014, EPRI conducted
more in-depth fault trials using
the test pump to assess the virtual
sensor model’s response to mass
unbalance, wear ring erosion, and
simulated cavitation damage. Of
these trials, mass unbalance proved
to be the only fault that produced a
large enough vibration output that
could be picked up by the installed
sensors and then correlated with the
virtual sensor model. Although the
model’s correlation for this fault
was promising, the team agreed that
additional trials would be required
to validate the capabilities of this
technology. More information is
available in Pump Virtual Sensors
Project:
Feasibility
Results
(3002004993).
Activities in 2015 will explore
additional faults, refine the model,
and examine whether outputs from an
additional monitoring technology –
motor current signature analysis (MCSA)
– could be incorporated into this virtual
sensor.
Contact: Jeff Greene, EPRI,
telephone: (704) 595-2666, email:
.
Attack Surface
“Attack surface” is a term that has
gained traction in the world of cyber
security. It refers to the various points or
vectors through which an unauthorized
user can try to enter data to or extract
data from an environment. For example,
a valve actuator at a nuclear plant has
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