Simulator 16 User Guide - PowerWorld

found on the Common Options sub-tab of the Setup tab. They could also be affected if choosing to
use merit order dispatch in which unit limits are always enforced.
SRT - Indicates that a solvable reverse transfer has been found when choosing to use the reverse
transfer option found on the Advanced Options sub-tab of the Setup tab. This message is appended
with the original critical reason that required the use of the reverse transfer.
RT Source Maxed - Indicates that the source no longer has enough resources to continue the
power transfer when using the reverse transfer option found on the Advanced Options sub-tab of
the Setup tab. This message is appended with the original critical reason that required the use of the
reverse transfer.
RT Sink Maxed - Indicates that the sink no longer has enough resources to continue the power
transfer when using the reverse transfer option found on the Advanced Options sub-tab of the Setup
tab. This message is appended with the original critical reason that required the use of the reverse
transfer.
Reached Nose in Base Case - This message will only occur for a contingency scenario. It
indicates that the contingency scenario is actually less limiting than the base case scenario and that
the analysis of the contingency scenario cannot continue because of the base case limitation. The
power transfer is always ramped in the base case prior to implementing the contingency. The
contingency cannot be attempted unless the base case solves with the transfer implemented.
Max Shift
This value will only be filled in for critical scenarios. This is the nominal shift that was implemented
to reach the critical scenario. The nominal shift is the actual accumulated transfer that was
attempted.
Note: With a few exceptions, shift values (includes Max Shift, Max Export, and Max Import) that are
reported are from the last solved solution before the critical point was reached. Because the critical
point is not considered a valid solution, no valid shift can be determined at this point. Therefore, the
values that are reported are as close to this point as the process can get within the tolerances
specified for the transfer step size. Exceptions to this occur when using the reverse transfer option.
In this case, the values that are reported are for the minimum transfer level at which the
contingency will solve and all voltages are adequate. Another exception occurs when a scenario
becomes critical because of inadequate voltages at the zero transfer level. Because the scenario can
be solved at this point, the shift values will be recorded at the actual step at which the voltages are
inadequate. If a case becomes critical due to inadequate voltages and is not at the zero transfer
level, the shift values reported for these will follow the rule that they come from the last solved step
at which all voltages were adequate. The recording of values determined by Quantities to Track will
also follow these same rules.
If a scenario is critical because either the source or sink does not have enough resources to continue
the power transfer, the shift values and tracked quantities that are reported are at the maximum
transfer level that can be achieved without source and sink limits being violated.
Max Export
This value will only be filled in for critical scenarios. This is the amount that the injection changed in
the source injection group due to the transfer and contingency implementation. This value's
magnitude can differ from the Max Shift value due to injection changes resulting from make-up
power requirements from the contingency.
See note with Max Shift for additional explanation on how shift values are recorded.
Max Import
This value will only be filled in for critical scenarios. This is the amount that the injection changes in
the sink injection group due to the transfer, loss changes due to the transfer, and contingency
implementation. This value's magnitude can differ from the Max Shift value due to the injection
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