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 Transfer, Multiple Meters
The Single Transfer, Multiple Meters tab shows the effect of a single transfer of real or reactive power on all the voltages in the system. To specify the transfer, choose the Seller and Buyer in the same manner done on the Power Transfer Distribution Factors dialog. Then specify whether the calculation of Real Power (P), Reactive Power (Q), or both are of interest.
Click Calculate Sensitivities to perform the calculations.
After clicking Calculate Sensitivities, each row of the results gives the sensitivity of voltage at the respective bus to the power transfer defined by the seller and buyer. The bus columns (to add see Display/Column Options) of interest after this calculation include:
- Sensitivity: Transfer dV/dP (per unit/MW) --> VP Sensitivity gives the sensitivity of voltage to a real power transfer
- Sensitivity: Transfer dV/dQ (per unit/Mvar) --> VQ Sensitivity gives the sensitivity of voltage to a reactive power transfer
- Sensitivity: Transfer dAngle/dP (radians/MW) --> AngleP Transfer Sensitivity gives the sensitivity of voltage angle to a real power transfer
- Sensitivity: Transfer dAngle/dQ (radians/Mvar) --> AngleQ Transfer Sensitivity gives the sensitivity of voltage angle to a reactive power transfer
The check box option Set generators off AVR and continuous switched shunts to fixed at buses participating in the transfer is also available. Selecting this option will turn off AVR control for generators and continuous switched shunts at buses containing generators participating in the transfer with a non-zero participation factor, resolve the power flow, calculate the voltage sensitivities, turn the AVR control back on for those generators and switched shunts for which it was changed, and then resolve the power flow. Stated another way, this option assumes that all generators and switched shunts at buses participating in the transfer maintain a constant reactive power output and do not maintain their voltage setpoint. With this option, affected buses become PQ buses instead of PV buses in the Jacobian. PV buses will have a zero sensitivity to injection changes because the voltage is fixed at the regulated setpoint, so in order to actually determine the impact of the injection at these buses, they need to be made into PQ buses.
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 transactor lists when either the Seller or Buyer type is Bus.
Self Sensitivity
The Self Sensitivity tab shows the effect of an injection of real or reactive power at a bus on its own voltage (assuming everything is absorbed at the island slack bus). It processes through each bus calculating its own self-sensitivity only.
Each row of the results gives the sensitivity of voltage at the respective bus to a power injection at the same bus. dV/dP gives the sensitivity of voltage to real power injection and dV/dQ gives the sensitivity of voltage to reactive power injection. To speed up the calculation, sensitivities are calculated only for the buses displayed in the Bus Sensitivities grid. The bus columns (to add see Display/Column Options) of interest after this calculation include:
- Sensitivity: Self dV/dP (per unit/MW) --> dV/dP gives the sensitivity of voltage magnitude to an injection of real power
- Sensitivity: Self dV/dQ (per unit/Mvar) --> dV/dQ gives the sensitivity of voltage magnitude to an injection of reactive power
- Sensitivity: Self dAngle/dP (radians/MW) --> dAngle/dP gives the sensitivity of voltage angle to an injection of real power
- Sensitivity: Self dAngle/dQ (radians/Mvar) --> dAngle/dQgives the sensitivity of voltage angle to an injection of reactive power
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.