Simulator 16 User Guide - PowerWorld

A field, EPC File\EPC Modification Status, is populated to indicate whether an object is
new or modified while reading. Even though this is a field that is normally associated with
loading in an EPC file, the meaning is the same so the same field is used.
Saving
When saving a case as a PTI RAW files the switched shunt records will always write out at
least one block. If none exists, a single block with 1 step and size equal to the present MVar
output is written.
GE PSLF Format (*.epc)
Reading
If the latitude and longitude values are both zero when loading an EPC file, both entries will
be ignored as invalid..
A designation of the area and zone of a GE branch and transformer will be stored when
loading from an EPC file.
When loading multi-terminal dc lines from an EPC file, current limits for dc converters will
not be enforced. This is set via a field, Enforce Current Limit, available with dc
converters.
When reading in a GE EPC file, the "aloss" parameter is usually rounded to one bus or the
other to be expressed in terms of the "From End Metered" field (except in the case of Multi-
Terminal DC converters).
Simulator does not consider load IDs to be case sensitive. If multiple loads are found with
the same ID that vary only by the case of the characters, Simulator will attempt to create a
unique ID for each load. An appropriate message will appear in the message log.
Appending
Appended data completely overwrites an existing record corresponding to the same bus
number(s).
Branch elements are appended to a case only if both of their terminal buses exist.
Any new buses or branches that are created are now flagged as having just been added.
This flag is then used as part of the pre-processing feature in the power flow solution to
automatically estimate appropriate voltage magnitudes and angles for any existing or new
branches and buses that become newly energized.
A field, EPC File\EPC Modification Status, is populated to indicate whether an object is
new or modified while reading.
If a new three-winding transformer is entered which uses a bus number which is already
used as a star bus by another three-winding transformer this will not be allowed and a new
bus number will automatically be chosen.
If appending an EPC file causes a transformer branch to be converted to a normal branch, a
log warning message will show this.
If the scheduled voltage for a bus is specified, the voltage setpoints for switched shunts and
generators that are regulating this bus are also properly updated.
Saving
When saving a case as a GE EPC file the Multi-Terminal DC converters will write out the
"aloss" parameter in a manner consistent with the EPCL file mtTAP.p
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