See Also
Displays OPF specific information about each generator record with a valid area/zone/owner filter. To show this display select Optimal Power Flow > Results > Generator Records in the Model Explorer. The OPF Generator Records Display is a class of Case Information Display and therefore can be used in a manner consistent with the other case information displays. Specific formatting options are available from the local menu, which can be accessed by right-clicking on any field in the display.
By default the display contains the following fields:
Number, Name
Number and name of the bus to which the generator is attached. The display's local menu offers you the opportunity to view the Quick Power Flow List and the Bus View Display for this bus. You can also use the local men to view the generator's dialog.
ID
Alphanumeric ID used to distinguish multiple generators at the same bus.
Area Name of Gen
Name of the generator's area.
AGC
Designates whether the generator's real power output is governed by automatic generation control (AGC). If the AGC field is set to Yes the generator is on AGC in the standard power flow. When a generator is on AGC its real power output is varied automatically, provided the generator is part of an area or super area that is also on automatic control.
In Simulator OPF the default operating mode is that only generators on AGC control are eligible to be OPF controls. In addition, the generator's area or super area must have AGC Status of "OPF". However in rare instances you may wish to always make a generator available for control or never make the generator available for control. This value is specified using OPF MW Control field.
Fast Start
Designates whether the generator is available as a Fast Start generator during the OPF solution process. Fast start generators are another type of control available to the Optimal Power Flow solution routine. The OPF routine can determine if a generator labeled as a fast start generator would be beneficial in reducing the overall system costs of generation dispatch. If a fast start generator is off-line, but could reduce the cost of the system, then the OPF routine will turn on the generator, and increase the generator's dispatch towards optimizing the system generating cost. Conversely, if a fast start generator is on-line, and the OPF routine determines that reducing the generator's output to 0 would reduce the total generation cost, then the OPF routine will shut off the generator.
Generally speaking, the fast start options should only be used with units with zero Minimum MW limits. Hence it is really aimed at hydro units, or small units which do not need a non-zero minimum MW output for valid operation. This requirement is needed because changing a unit's status is only valid in the OPF routine if it is determined that the unit should dispatch 0 MW to optimize the generating costs of the system.
OPF MW Control
Designates whether the generator's real power output should be included as a control variable in the OPF. This field, which can be toggled, has three possible values:
- "If AGCable" - Generator's control availability depends upon its AGC status.
- "Yes" - Generator is available as a control, regardless of its AGC status.
- "No" - Generator is NOT available as a control, regardless of its AGC status.
Note: in order to be a control the generator must also be in an area or super area on "OPF" control.
Gen MW
The real power output of the generator.
Cost Shift $/MWh, Cost Multiplier
The cost shift and cost multiplier allow you to easily apply a shift to the cost function for the purpose of assessing how variations in bids impact profit. The cost function is affected based on the following equation:
(Original Cost Function + Cost Shift) * Cost Multiplier
Cost $/Hr
The total cost of the generator, including the impact of the cost shift and cost multiplier.
MW Marg. Cost
Tells the marginal cost, in $ / MWhr, to supply one additional MW of load at this bus. If a generator is available as a control and is not at either its minimum or maximum limit or a cost model breakpoint, then the MW Marg. Cost field will be identical to the generator's current marginal cost. However the usual case is for the generator to be at either a limit or a cost model breakpoint so the usual situation is that the MW Marg. Cost field values IS NOT equal to the generator's marginal cost.
IC for OPF
Incremental cost of the generator at its current operating point.
Initial MW
The initial real power output of the generator at the beginning of the OPF solution. You can reset the case back to these values by selecting the LP OPF, Restore Previous Control Settings menu item. This menu item is only available following a successful OPF solution.
Initial Cost
The initial generator cost at the beginning of the OPF solution.
Delta MW
Change in the generator's real power output as a result of the OPF.
Delta Cost
Change in the generator's cost as a result of the OPF.
Min MW, Max MW
Minimum and maximum real power output of the generator.
Cost Model
The current cost model being used for the generator. The field value is either "Cubic", indicating that the generator's operating costs are being modeled using a cubic cost function, or "Piecewise Linear", indicating the operating costs are being modeled using a piecewise linear cost function. Toggle the field to change the model. Note that a generator may simultaneously have a cubic model and a piecewise linear model.
Because the OPF uses a linear programming approach, the generator's operating costs are ALWAYS modeled using the piecewise linear model. Generators with an existing cubic cost model are either 1) ignored as OPF controls, or 2) have a piecewise linear cost model automatically created from the cubic model, depending upon the values specified on the OPF Options and Results Dialog.
# Cost Curve Points
Shows the number of segments in the piecewise linear model. If no piecewise linear model exists then this field is zero; the generator's costs are being modeled using the cubic function. For such generators you can automatically setup a piecewise linear model simply by entering a non-zero value for the number of points. A piecewise linear model is created that matches as closely as possible the existing cubic model.
Fuel Type
Specifies the fuel type of the generator, if it is known; double-click to toggle through the options. Options are Unknown, Coal, Gas, Hydro, Hydro Pumped, Nuclear, Petroleum, Solar, Wind, and Other.
Profit $/hr
Shows the profit of the generator. Profit is calculated using this equation:
Profit = (GenMW * MW Marg Cost ) – [ Evaluation of the Generator Cost Function ]