Disregard an Object

This guide shows how to disregard an object (e.g, generator, demand, lines, etc.) or a service (ancillary service, constraint, etc.) in the SAInt GUI. When disregarded a particular object or service is set to out of service and will not be considered by the solver during the simulation or optimization.

1. Set a network object to out of service

A network object in SAInt can be set to out of service by unchecking the InService property flag, from the property editor of a network object. An example property editor of a fuel generator (FGEN) is shown in Figure 1.

While working with SAInt API, the user can set the property InService to FALSE of network objects with a parameter import file.

The change in InService property is applied at a network level and is considered for all the linked scenarios.

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Figure 1. InService property in the property editor

1.1. Additional rules for nodes and externals

Nodes

If a node is set to out of service, the externals and branches connected to the node are not considered by the solver, even if the InService property flag for externals and branches is checked.

To completely disregard a portion of the network from the analysis, like to model retirement of a gas pipeline (GPI) and all the gas externals (GXT) down the line, it is necessary to uncheck the property InService of both the gas node GNO and the GPI. Thus, the solver will not calculate the pressure and the flow at the GNO.

Externals

If an external is set to out of service, it is not considered by the solver. However, in case of a hydro generator (HGEN) and fuel generator (FGEN), additional dependency on a hydro plant (HYDP) and fuel (FUEL) is considered.

HGEN

The solver does not consider the HGEN if the linked HYDP is set to out of service.

FGEN

The solver does not consider the FGEN if the linked FUEL is set to out of service.

2. Create an OFF event for a network object

A network object can also be disregarded at a scenario level via a scenario event. In SAInt, almost all network object that can be set to out of service also has an associated scenario event to turn OFF the object during or at the start of the simulation or optimization. Figure 2 shows an example of creating an OFF event for an electric line (LI). The same steps can be followed to create an OFF event for any applicable network object.

Additional rules for nodes and externals are also true in case of an OFF event.

For nodes, click on Scenario Event  Turn off connected externals (OFF) from the context menu.

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Figure 2. Scenario event to turn OFF a network object.

To consider a network object during the simulation or optimization following an OFF scenario event, an ON event can be included. However, an ON event is not considered if a network object has been set to out of service at a network level through the InService property flag.

For gas scenarios, the OFF event means that the solver considers the object, e.g., GCS or GXT, with a flow rate equal to zero.