Simulator 16 User Guide - PowerWorld

where an individual limiter is being iterated on. If using the Iterated Linear Step (IL) then
Full CTG method this is the step that occurs before actually applying the contingency. The
Transfer Limit that is reported is the total amount that could be ramped before the power
flow failed to converge. This transfer limitation means that the full desired transfer amount
cannot be achieved.
RAMP_FAIL_IN_FULL (fuchsia) - If using the Iterated Linear Step (IL) then Full CTG
method and forcing the transfer ramping to occur pre-contingency, this type of limiter will
occur only when iterating on individual limiters. This indicates that the power flow was not
able to solve while ramping the transfer and not because the contingency failed to solve.
The Transfer Limit that is reported is the accumulated transfer amount that has been
ramped as of the last successful solution at which the contingency solved.
RAMP_FAIL_IN_BASE (gray) - This type of limiter will not be reported for new studies
run with Simulator version 16 or later. It is being retained for the purposes of reporting
limiters that were saved with Simulator version 15 and earlier. This type of limitation is the
same as a POWERFLOW_DIVERGENCE limiter and would only be reported for a transfer
limitation for the base case or when using the Iterated Linear Step (IL) method.
RAMP_FAIL_IN_FULL_AFTER_CTG (gray) - This type of limiter would only be reported
if using the Iterated Linear Step (IL) then Full CTG method and ramping the transfer postcontingency
when the full ramping amount cannot be achieved. The Transfer Limit that is
reported is the total amount that could be ramped before the power flow failed to converge.
CTG_FAIL_IN_FULL (orange) - Indicates that the contingency failed to solve at some
point during the Iterated Linear Step (IL) then Full CTG method. This type of limiter would
be reported when NOT using the option to iterate on failed contingencies. The Transfer
Limit that is reported is the accumulated transfer amount that has been ramped as of the
last successful solution in which the contingency solved. If the contingency fails to solve
immediately following the completion of the iterated process on the individual limiter
without the contingency implemented, the Transfer Limit that is reported is the
accumulated transfer amount achieved from that process without the contingency
implemented.
CTG_FAIL_ITERATED (red) - Indicates that the contingency failed to solve at some point
during the Iterated Linear Step (IL) then Full CTG method and using the option to iterate on
failed contingencies. The Transfer Limit that is reported is the accumulated amount that is
possible without overloading the monitored element and in which the contingency solves.
Using the iterated method attempts to get as close as possible (within specified tolerances)
to the highest transfer amount at which the contingency will solve. This is very similar to a
PV nose point.
CTG_FAIL_IN_BASE (purple) - Indicates that the contingency failed to solve at zero
transfer level (base case failure) when using the Iterated Linear Step (IL) then Full CTG
method and choosing to iterated on failed contingencies. The Transfer Limit that is reported
is the accumulated transfer amount that was ramped during the iterated process on the
individual limiter without the contingency implemented.
Limiting Element (shown by default)
Shows a text description of the limiting element. This will contain either the actual limiting
element or some additional information about a limiter. Special keywords that can appear are
OSCILLATING and POWERFLOW DIVERGENCE. There are described in more detail above in the
Transfer Limit description. If reporting reserve limits and either the source or sink will hit a
reserve limit at a particular transfer level, the name of the source or sink will appear as the
limiting element.
Limiting CTG (shown by default)
Shows the name of the limiting contingency.
% OTDF (shown by default)
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