AM/FM/GIS Modeling to support Power System Planning
John W. Hardin
Intergraph Public Safety
Mailstop LR23A1
One Madison Industrial Park
Huntsville, Alabama 35894-0001
Karen Bachmeyer
Intergraph Public Safety
Mailstop LR24B2
One Madison Industrial Park
Huntsville, Alabama 35894-0001
Abstract
The GIS contains a warehouse of geographic based information that is tracked in
numerous systems throughout the utility. With some common sense modeling
techniques, a basic appreciation of circuits, and knowledge of the vendor specific
analysis package, this data can support electrical analysis.
Often, the facility data is simply extracted from the GIS to an analysis package to
perform load flow analysis, fault analysis, motor start analysis, capacitor
placement optimization, and switching optimization. With current architectures,
these capabilities can be built into the GIS providing the distribution engineer a
set of powerful analytical tools in a single environment.
In addition, switching status from the outage system and metered data from
SCADA/MV90 can be leveraged to analyze summer and winter, heavy and light-loading
situations. Transformer load statistical analysis output can be used to
derive load data for the electrical analysis.
Modeling GIS Data to support Analysis
The GIS contains a warehouse of geographic based information that is tracked in
numerous systems throughout the utility. With some common sense modeling
techniques, a basic appreciation of circuits, and knowledge of the vendor specific
analysis package, this data can support electrical analysis.
Common Sense Modeling Techniques
Most GIS facilities represent items of plant, though some are only logical. When
it is possible, model electrical devices as they exist in the field. This will simplify
the maintenance of the data in the GIS. Also, it increases the likelihood that you
will later be able to look-up electrical properties for analysis using standards
books.
Try to keep things as simple as possible. For example, let us examine the
modeling of switchgear. Typically, switchgear is purchased as a single unit.
However, the connectivity of switchgear is relatively complex and the switches
and/or fuses contained in switchgear may be replaced individually. If you model
the switchgear as a composition of buses, fuses, and switches, modeling the
connectivity becomes simple. To avoid confusion in the GIS, most companies
place a logical facility representing the switchgear cabinet to tie everything that
composes the switchgear back together though the switchgear cabinet is not part
of the electrical model.
A good question to ask yourself as you are designing the GIS facilities for
electrical modeling is, “How will this data be maintained?”. Since much of the
information you need may be known by field personnel, you may need to
examine your work processes to make sure that this information is maintained in
the GIS whenever feasible. Part of determining the feasibility of collecting the
data is weighing the cost of maintaining the data against any benefit you may
achieve. If you determine you cannot maintain the data over the long haul, then
you need to re-think what you are doing.
