Simulator 16 User Guide - PowerWorld

Difference Flows: Case Types
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 case types is currently being
displayed. 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.
The case types available are:
Base Case – A solved power system that serves as the reference for the difference flows tool. To
establish a base case, set up a solved power system corresponding to the desired operating point.
Open the Difference Flows Dialog and click the button labeled Set Present as Base Case.
Present Case – The operating point used in the Difference Flows comparison. Note: The Present
Case must have the same numbering scheme as the Base Case for proper operation of the
Difference Flows tool. See Topological Differences for more information.
Difference Case – The difference between the Present Case and the Base Case values. The
values displayed in the Difference Case are established using the Base Case as the reference.
When showing status fields for branches, generators, etc... fields will show up as either
OPEN/CLOSED or CLOSED/OPEN if the status changed. The status in the present case will be listed
first. A similar format will be used for fields such as generator AGC Status and other text fields.
To toggle between the different case views, open the Difference Flows Dialog and select the desired
case type. Alternatively, you can click the Difference Flows button in the Other Tools Ribbon Group
on the Tools ribbon tab and select the desired case type.
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