Simulator 16 User Guide - PowerWorld

Difference Flows
The Difference Flows feature provides an easy mechanism for comparing two power system cases.
For example, Difference Flows can be used to show the difference in transmission line flows and bus
voltages resulting from a contingency or a change in power transfer between two areas. Difference
Flow is available in both Run Mode and Edit Mode, however when you switch from Run Mode back to
Edit Mode, Simulator automatically resets you to the Present Case. This is done so that you do not
accidentally try to edit data while in Difference or Base Case mode. Once you are in Edit Mode
however, you can still manually switch back to Difference or Base Case Mode.
For more information about how to use Difference Flows see Using Difference Flows.
The Difference Flows Dialog can be accessed by:
Go to the Tools ribbon tab, and choose Difference Flows > Difference Flows from the Other
Tools Ribbon Group. .
Selecting Difference Flows from the oneline local menu.
All Difference Flows Actions are controlled via the Difference Flows Dialosg or the drop-down list
on the Difference Flows toolbar button.
Case Type to Display
Use of this feature affects all aspects of the Simulator environment. When using the Difference
Flows tool, information shown on oneline diagrams, case information displays, and power flow lists is
governed by which of the three Difference Flow Case Types (base, present or difference) is currently
being displayed.
Key Field to Use
The difference flows feature must make a comparison between the Present Case and the Base Case
to determine which objects between these two case match one another. The Key Fields to Use
specifies whether this matching is done using Primary Keys (bus numbers), Secondary Keys (bus
names/Nom kV pair), or by Label.
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