Simulator 16 User Guide - PowerWorld

Power Flow Solution: Island-Based AGC
The following options are all contained on the Island-Based AGC tab after choosing the Power Flow
Solution page of the Simulator Options.
The Island Based AGC options allow the user to choose to dispatch generation by island instead of by
area or super area. The options available for dispatch here are:
Disable (Use the Area and Super Area Dispatch Settings)
When this option is selected, Island Based AGC is being used, and generators are dispatched
according to the usual area or super area generation dispatch.
Use Participation Factors of individual generators
When selected, the island-based AGC is used, based on the individual participation factors of each
generator within the island. Area and super area ACE requirements will be ignored, and all
generators in the island will be dispatched to serve load, losses, and any DC transfers to other
islands.
Note that if all generators with AGC = YES have participation factors also equal to 0.0, then all
make-up power will come from the island slack bus.
Calculate Participation Factors from Area Make Up Power Values
The AGC will dispatch generation by use area make up power values, instead of by individual
participation factor. What this means is that each area will be assigned a make up power value,
similar to assigning a participation factor to a generator. Based on the make up power value of each
area in the island, the amount of the generation dispatch needed will be divided amongst each area
based on its value. Higher value will account for more of the generation dispatch than areas with
smaller values. The within each area, the generation dispatch is handled on an individual generator
participation factor basis, where each generator will account for a portion of the dispatch that was
assigned to its area.
To specify the make up power values for each area, click on the Specify Are Make Up Power
Values button. Note that these settings are the same as those used by Contingency Analysis
Options Make Up Power, therefore changing these values will affect the contingency analysis.
For example, three areas have participation factors of 2, 1 and 1, respectively. If the total
generation redispatch in the island is 100 MW, then area 1 will account for 2 / (2+1+1), or 50%, of
the total. Therefore area 1 is expected to redispatch by 50 MW. If area 1 then has two generators
with participation factors of 4 and 1, they will account for the 50 MW by picking up 4 / (4+1) and 1 /
(4+1), or 80% and 20%, respectively, of the 50 MW needed from the area.
Note that if all areas have CTG Make Up Gen equal to 0.0, then all make-up power will come from
the island slack bus.
Dispatch using an Injection Group (Loads and Generators will respond)
Checking this option will allow for the island dispatch to be covered by change in generation and/or
load defined in an injection group.
Additional options are available when dispatching based on an injection group:
Allow only AGC Units to Vary
If this option is checked, only units whose AGC status is turned on will be allowed to participate
in the injection group dispatch.
Enforce unit MW limits
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