Generator bus type used in modeling the power flow simulation. When you select a particular model, those fields that do not apply become unavailable.

• Swing - A swing bus holds the bus voltage and angle constant. To do this there cannot be limits on the amount of MW or MVAR the swing machine can accept or provide. (See Swing Sources.)
• PV - Constant power, constant voltage generator. This is also known as a regulated generator. This model tries to hold a user-specified bus voltage within generator MVAR limits.
• PQG - Constant power, constant var generator. This is also known as an unregulated generator. This model holds the MVAR generation within given voltage limits.

Desired control voltage for a regulated generator (PV). The generator will try to control the voltage at the controlled bus to a given value. If the generator bus is the swing bus, this voltage serves as the reference voltage. The voltage is entered in per-unit.

Controlled angle is used only when a generator is designated as a swing bus. The value is entered in degrees.

For a PV generator (regulated), the bus that is to be controlled to the control voltage. If this field is blank in the database, EasyPower fills it in with the name of the bus listed in the To Bus field. (Note that this does not take effect until you accept it by clicking OK to close the database dialog box.)  This field is ignored if the Model is set to Swing.

Note: To set the control bus for a single-phase utility or generator, you must make the connection on the one-line. .

Generator output MW. This may be actual operating or a rated value. This applies only to a PV or PQG generator.

Generator output MVAR. This is only used when the generator is a constant power, constant var (PQG) machine or when a PV generator MVAR limit has been reached and the machine automatically switches to PQG.

DC generators have three control modes:

• Swing (Regulated): The voltage is controlled directly on the terminal of the generator. A regulated DC generator has the ability to be the single source that enables a system to enter power flow and solve the system.
• Swing (Un-Regulated): The voltage is held constant internally as a Thevenin source. The terminal of the generator changes with loading. An un-regulated DC generator has the ability to be the single source that enables a system to enter power flow and solve the system.
• Constant Power: The generator is modeled as a constant power generator, similar to a PQ generator in the AC power flow. A constant power DC generator DOES NOT have the ability to be the single source that enables a system to enter power flow and solve the system. To enter power flow focus, at least one other source must be modeled that supplies the system with stiff internal or external source.

This is the scheduled per-unit voltage that the voltage control unit will try to maintain for the generator. This applies only to the Swing (Regulated) model.