Contingency Element Type: Load

 

The following describes the options available when creating a contingency element of type Load. 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 load to Open if the load Status is Closed. If the load 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 load 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 load to Closed if the load Status is Open. If the load 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 load 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 load from an existing load bus to another bus by a specified Amount. A load move can be done on a bus basis (impacting the total load of all loads at the selected bus) or can be targeted at a specific load. Load may be moved in MW (const pf), Percent,MW, or Mvar. The load amount that is moved is the total actual load and may be different than the nominal load if the area of the load has a Load MW Multiplier other than 1.0 or the load contains constant impedance or constant current components. If there is no on-line load at the selected load bus or the bus at which the load is located is Open, no load move will occur. A MW (const pf) move will move the specified amount of load MW to the Bus to Move to while moving a Mvar amount that will maintain a constant power factor at the selected load bus. A Percent move will move the specified percent of the contingency reference state load MW and Mvar to the defined Bus to Move to. A MW move will move the specified amount of the load MW to the Bus to Move to. A Mvar move will move the specified amount of the load Mvar to the Bus to Move to. The Move amount can be either positive or negative. A positive amount will decrease the load at the selected bus, and a negative amount will increase the load at the selected bus. The Bus to Move to will respond accordingly.

If a load already exists at the bus to which the load is being moved, the load at that bus is adjusted according to the move amount. If no load exists, then a load is added at the bus and the load is set 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’ load parameters to a specified Amount. Load Set To actions can be done on a bus basis (impacting the total load of all loads at the selected bus) or can be targeted at a specific load. Load parameters can be set in MW (const pf), Percent, MW, or Mvar. The load value that is set for each of these options is the actual constant power component of the load. This value may be different than the nominal constant power component of the load if the area that contains the load has a Load MW Multiplier other than 1.0. If there is no on-line load at the selected load bus and the bus at which the load is located is Closed, load status at the selected load bus will change so that one load is Closed and the total constant power load at the bus will be set to the specified amount. If the bus at which the load is located is Open or there is no existing load, either Open or Closed, at that bus, then no load change will occur. When the load is set in MW (const pf), the actual constant power MW will be set to the specified amount and the actual constant power Mvar will be set so that a constant power factor is maintained at the load bus. When the load is set in Percent, the actual constant power MW and Mvar will be set to the specified percent of the contingency reference state load MW and Mvar. When the load is set in MW, the actual constant power MW at the selected load will be set to the specified amount. When the load is set in Mvar, the actual constant power Mvar at the selected load will be set to the specified amount.

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 load due to the contingency action.

Change By

The Change By action will change the selected bus’ load parameters by a specified Amount. Load Change By actions can be done on a bus basis (impacting the total load of all loads at the selected bus) or can be targeted at a specific load. Load parameters can be changed in MW (const pf), Percent, MW, or Mvar. The load value that is changed for each of these options is the actual constant power component of the load. This value may be different than the nominal constant power component of the load if the area that contains the load has a Load MW Multiplier other than 1.0. If there is no on-line load at the selected load bus or the bus at which the load is located is Open, no load move will occur. When the load is changed in MW (const pf), the actual constant power MW will be changed by the specified amount and the actual constant power Mvar will be changed so that a constant power factor is maintained at the load bus. When the load is changed in Percent, the actual constant power MW and Mvar will be changed by the specified percent of the contingency reference state load MW and Mvar. When the load is changed in MW, the actual constant power MW at the selected load bus will be changed by the specified amount. When the load is changed in Mvar, the actual constant power Mvar at the selected load bus will be changed by the specified amount.

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 load due to the contingency action.