See Also
To access the Flows and Voltages Sensitivities dialog go to the Tools ribbon tab, and choose Sensitivities > Flows and Voltages Sensitivities from the Run Mode ribbon group. This is only available in Run Mode.
The grids that occupy all of the tabs on this dialog list each device of the particular type in the system, subject to the Area/Zone/Owner Filter settings. These grids are case information displays, and thus share properties and controls common to all other case information displays.
Single Meter, Multiple Transfers
The Single Meter, Multiple Transfers tab shows the effect an additional injection of real or reactive power at a bus has on various parameters. If a bus is a PV bus, instead of determining the impact that additional injection of reactive power at the bus has, the impact of changing the voltage setpoint at the bus is determined. Additionally, the sensitivities of the Flow Type will be determined due to phase shifter phase, transformer tap, and switched shunt nominal injection changes.
Device Type and Associated Flow Type
The following device types can be selected with their associated Flow Type.
Line/XFMR
MW - real power flow on the branch
Mvar - reactive power flow on the branch
MVA - apparent power flow on the branch
Interface
MW - real power flow on the interface
Mvar - reactive power flow on the interface
MVA - apparent power flow on the interface
Bus
Magnitude - voltage magnitude in per unit at the bus
Mvar - reactive power injection at the bus
Generator
Mvar - reactive power injection at the generator. When determining this sensitivity, the sensitivity of the total Mvar injection at the generator bus is determined. This is the same value that would be returned if picking Device Type of Bus and Flow Type of Mvar. This total is apportioned to specific generators at a bus based on their proportion of the total Mvar range for the bus. Only generators that are online and on AVR control are included in the calculation.
After selecting a Device Type, a particular device must be selected from the object chooser.
Whenever you make a change to any of these settings, click Calculate Sensitivities to update the grids with the new sensitivities.
Buses Tab
The buses tab provides sensitivities for injecting real or reactive power at a bus or changing the voltage setpoint at a bus. All injections assume that the power is absorbed at the island slack bus.
The bus fields (to add see Display/Column Options) of interest after this calculation include:
- Sensitivity: Injection dValue/dP -->(P Sensitivity) gives the sensitivity of the selected Flow Type to an injection of real power at the bus selected in the row of the results
- Sensitivity: Injection dValue/dQ --> (Q Sensitivity) gives the sensitivity of the selected Flow Type to an injection of reactive power at the bus in the row of the results. This value is only calculated for PQ buses.
- Sensitivity: Injection dValue/dVsetpoint (for PV bus) --> (V Sensitivity) gives the sensitivity of the selected Flow Type to a change in voltage setpoint at the bus in the row of the results. This value is only calculated for PV buses.
- Sensitivity: Injection dAngle/dP (radians/MW) --> (AngleP Sensitivity) gives the sensitivity of voltage angle to an injection of real power at the bus in the row of the results. This value is only calculated when the Device Type is Bus and the Flow Type is Magnitude.
- Sensitivity: Injection dAngle/dQ (radians/Mvar) --> (AngleQ Sensitivity) gives the sensitivity of voltage angle to an injection of reactive power at the bus in the row of the results. This value is only calculated when the Device Type is Bus and the Flow Type is Magnitude.
The option labeled Set Out-Of-Service allows you to approximate the sensitivities at out-of-service buses with the sensitivity of the closest bus. Otherwise the out-of-service buses will display sensitivities of 0 when the sensitivities are calculated.
If the Integrated Topology Processing add-on is available, the Only show the primary bus for each superbus checkbox will be available. When checked, the buses that show up in the table will be limited to only those that are primary nodes. The determination of primary nodes is based on the base case topology. This provides an easy filter to eliminate redundant data. This option also limits the buses that appear in the chooser list when the Device Type is Bus.
Generators Tab
The generators tab provides the same sensitivity information that is available on the Buses Tab except that only generator buses are listed. This provides an easy way to filter out only generator buses.
Loads Tab
The loads tab provides the same sensitivity information that is available on the Buses Tab except that only load buses are listed. This provides an easy way to filter out only load buses.
Phase Shifters Tab
This tab provides a listing of all phase shifters in the case. The Sensitivity: Flow/Voltage with respect to Phase --> Sensitivity/Degree field gives the sensitivity of the Flow Type to a change in phase shifter phase.
LTC Transformers Tab
This tab provides a listing of all transformers in the case. The Sensitivity: Flow/Voltage with respect to Tap --> LTC Sensitivity field gives the sensitivity of the Flow Type to a change in transformer tap.
Switched Shunts Tab
This tab provides a listing of all switched shunts in the case. The Sensitivity: Q Nominal Injection --> Q Sensitivity field gives the sensitivity of the Flow Type to a change in nominal Mvar injection at a switched shunt.