Electric Energy T&D - Index

Electric Energy T&D - EEMag March / April 2008 - Index

In addition to the automatic mapping, the system also handles all
necessary database partitioning, indexing, trimming and log deletion
automatically, so that no database administration time is needed to
maintain the system.
Although the system does occasionally require some maintenance
by Entergy and/or Nobadeer, the zero maintenance target has
very nearly been achieved, especially when considering the volume
of data captured.
Preserving the Security Perimeter
Pegasus has shown it can reliably collect, store and provide all of the
SCADA data to its internal users, so Entergy is now in the process of
retiring all of the old data gathering applications from the EMS. In the
future, the system will also provide information to all authorized T&D
users outside of the operations arena as well via the typical corporate
desktop. This helps Entergy meet the NERC Critical Infrastructure
Protection (CIP) guidelines by providing a clear separation (just two
logical connections) between critical and non-critical assets.
Access to the Data Store
In addition to a desktop client and the ability to move data from the
client to other desktop applications like Microsoft Access and Excel,
all data is available to other programs using a simple application
programming interface (API). Bulk exports of data are supported by a
dedicated Exporter application that uses this API. The Exporter allows
the user to gather, for example, all megawatt readings from a region
for a year with a simple command script. The API is also used by data
mining applications that operate on the data store.
Application Development Standards
Application development used modern tools and techniques, with
its processes programmed to take advantage of new multi-core CPU
technologies. The system is very stable, scalable, and shows excellent
performance with over one trillion records on-line. As the on-line
database grows, the data retrieval time remains constant – a feature
30 I March-April 2008 Issue
that required extensive effort to design and implement but that is
invaluable in such a dynamic data environment.
Enabling Success
The storage, retrieval and audit capabilities of the system are field
proven with over three years of on-line service. The ability to pull
massive sets of reliable, complete data from the system is being
increasingly recognized and used by the planning and maintenance
organizations at Entergy. Some of the successes include:
• Automated audit tracking of the SCADA database changes
• Reducing the need for SCADA support personnel to be involved
when T&D planning, maintenance or management organizations
request archived SCADA data across a wide time range. Compared
with the legacy system, which could only piece together data on a
day-by-day basis, a reliable and flexible interface to data on daily,
monthly or longer time frames is now readily available.
• Reliable and easy access to data has allowed various departments to:
- Start fine tuning alarm levels,
- Determine which transducers are out of calibration,
- Obtain data to support load balancing decisions that have
a direct effect on reliability,
- More effectively support the system design team,
- And, identify “chattering” alarms to speed up repairs.
Next Steps
At this point development is focusing on data mining applications that
take advantage of the tight integration of the system with Entergy’s
SCADA system to provide reports and automated analysis of how
well the T&D system is performing. Examples of data mining reports
already developed and going into production in Q1- 008 include:
• “Sticky” circuit breakers (i.e., breakers not responding properly to
operator commands). One click on this report brings up the list of
breakers with problems, and selecting any of these brings up the
OPEN/CLOSE history of that device for the month, showing each status
change and any related operator command. [Refer to Figure 3]
figure 3: The system provides numerous data mining reports. This example shows a drill down (detail) from the ‘No Response’ report, flagging a problem
by showing that Device J0434 required multiple close commands before the breaker operation was completed.