Modeling generator ON/OFF events over time

Hi @emmacooper,

Great question! This is a support request we’ve actually received before, although that was prior to the existence of this forum. Because we have received this request multiple times, we are considering adding support for this in the future. Currently there is no direct way to provide this input, but there is an indirect method that requires just a couple of additional steps.

Generator state Events (ON, OFF, and ONOFF) do not accept numeric values for their “Value” property. However, these can be configured to depend on the value of another property using the “Condition” and “Evaluation” properties of the Event.

We recommend using a “PREF” event to refer to the outage profile. A PREF Event in SAInt is a “passive” event that allows the user to define a value that can be referenced but does not affect the simulation. You can then define an OFF Event and either an ONOFF or ON Event that use the “Condition” of PREF = 1. See the example below where the OFF Event is used if PREF does not equal 1 and the ONOFF Event is used if PREF is equal to 1. This achieves the goal you are asking.

One quick note about ON versus ONOFF. An ON Event will force a generator to be on no matter what. An ONOFF event will specify that a generator is available but ultimately its ON or OFF status will be determined by the solver. This is the recommended behavior in most cases. Also note that for some object types, for example XGEN, PV, and WIND objects, it is not possible to define an ONOFF Event because these objects have no binary unit commitment variable associated with them.

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