Contingency Element Type: Switched Shunt

 

The following describes the options available when creating a contingency element of type Switched Shunt. Contingency elements are created from the Contingency Element Dialog, and additional details of how to create contingency elements can be found here.

 

Action Settings

Open

The Open action will set the Status of the selected switched shunt to Open if the switched shunt Status is Closed. If the switched shunt Status is already Open, this action does nothing.

When using the Open action, the Make-up Power Sources button is enabled and power sources can be specified to account for the changes in the real power portion of the switched shunt due to the contingency action.

Open Breakers

See the special topic on Open Breakers for more detail.

Close

The Close action will set the Status of the selected switched shunt to Closed if the switched shunt Status is Open. If the switched shunt Status is already Closed, this action does nothing.

When using the Close action, the Make-up Power Sources button is enabled and power sources can be specified to account for the changes in the real power portion of the switched shunt due to the contingency action.

Close Breakers

See the Close Breakers for Contingencies topic on the Contingency Element Dialog topic.

Move

The Move action allows the transferring of switched shunt MW and/or Mvar from an existing switched shunt bus to another bus by the specified Amount. A switched shunt move can be done on a bus basis (impacting the total shunt output of all switched shunts at the selected bus) or can be targeted at a specific switched shunt. During the move action, the nominal values of the switched shunts are adjusted, and switched shunts that are adjusted have their Control Mode set to Fixed. If there are no switched shunts at the selected switched shunt bus with a Status of Closed, no switched shunt move will occur. Switched shunt Moves may be done in Percent, MW, or Mvar. A switched shunt Move in Percent will move the specified percent of contingency reference state nominal MW and Mvar at the switched shunt bus to the defined Bus to Move to. A MW move will move the specified amount of switched shunt MW to the Bus to Move to. A Mvar move will move the specified amount of switched shunt Mvar to the Bus to Move to. The Move amount can be either positive or negative. A positive amount will decrease the nominal MW and/or Mvar at the selected switched shunt bus, and a negative amount will increase the nominal MW and/or Mvar at the selected switched shunt bus. The Bus to Move to will respond accordingly.

If a switched shunt exists at the bus to which the switched shunt MW and/or Mvar is being moved, the switched shunt at that bus is adjusted according to the move amount. If there are existing switched shunts at the Bus to Move to but all of them have a Status of Open, the first switched shunt Status will be set to Closed, the Control Mode will be set to Fixed, and the nominal MW and/or Mvar will be adjusted according to the move amount. If no switched shunt exists at the Bus to Move to, then the nominal constant impedance load is adjusted according to the move amount. If no switched shunt exists at that bus, then a switched shunt is added and the nominal injection is adjusted according to the move amount.

Move actions are not allowed for Contingency Primary Elements used with CTG Combo Analysis.

Set To

The Set To action will set the selected bus’ switched shunt parameters to a specified Amount. Switched shunt Set To actions can be done on a bus basis (impacting the total shunt output of all switched shunts at the selected bus) or can be targeted at a specific switched shunt. Switched shunts that are adjusted during Set To actions have their Control Mode set to Fixed. Switched shunt parameters can be set in Percent, MW, Mvar, or Setpoint Voltage. When a switched shunt bus is set in Percent, the nominal MW and Mvar are set to the specified percent of the contingency reference state nominal MW and Mvar of the switched shunt bus. When the switched shunt bus is set in MW, the nominal MW is set to the specified amount. When the switched shunt bus is set in Mvar, the nominal Mvar is set to the specified amount. When the switched shunt bus is set in Setpoint Voltage, the Target Value of the controllable switched shunt at the bus is set to the specified amount. Switched shunts may either regulate voltage or generator Mvar. The amount entered for the Setpoint Voltage is considered to be in per unit when the switched shunt is regulating voltage and is considered to be in Mvar when regulating generator Mvar. If there are no switched shunts at the selected bus with a Status of Closed when setting MW or Mvar amounts, the Status of the first switched shunt at the bus will be set to Closed, the Control Mode will be set to Fixed, and the nominal value will be set appropriately.

When using the Set To action, the Make-up Power Sources button is enabled and power sources can be specified to account for the changes in switched shunt MW due to the contingency action.

Change By

The Change By action will change the selected bus’ switched shunt parameters by a specified Amount. Switched shunt Change By actions can be done on a bus basis (impacting the total shunt output of all switched shunts at the selected bus) or can be targeted at a specific switched shunt. Switched shunts that are adjusted during the Change By action have their Control Mode set to Fixed. Switched shunt parameters can be changed in Percent, MW, Mvar, or Setpoint Voltage. When a switched shunt bus is changed in Percent, the nominal MW and Mvar are changed by the specified percent of the contingency reference state nominal MW and Mvar of the switched shunt bus. When the switched shunt bus is changed in MW, the nominal MW is changed by the specified amount. When the switched shunt bus is changed in Mvar, the nominal Mvar is changed by the specified amount. When the switched shunt bus is changed in Setpoint Voltage, the Target Value of the controllable switched shunt at the bus is change by the specified amount. Switched shunts may either regulate voltage or generator Mvar. The amount entered for the Setpoint Voltage change is considered to be in per unit when the switched shunt is regulating voltage and is considered to be in Mvar when regulating generator Mvar. If there are no switched shunts at the selected bus with a Status of Closed when setting MW or Mvar amount, the Status of the first switched shunt at the bus will be set to Closed, the Control Mode will be set to Fixed, and the nominal value will be set appropriately.

When using the Change By action, the Make-up Power Sources button is enabled and power sources can be specified to account for the changes in switched shunt MW due to the contingency action.