Simulator 16 User Guide - PowerWorld

Transformer AVR Dialog
The Transformer AVR Dialog is used to view the control parameters associated with load-tap-changing
(LTC) transformers when they are used to control bus voltage magnitudes. To view this dialog, click
the Change Automatic Control Options button found with the Transformer Control options,
provided that the Voltage Regulation (AVR) option is chosen from the Automatic Control Type
group.
The Common Options tab of this dialog has the following fields:
Automatic Control Type
This section is only visible on the dialog in edit mode. The control type of the transformer can be
changed between no control, voltage regulation, reactive power control, or phase shifter control.
Changing the control type will update the dialog to reflect the type of control that is selected.
Regulated Bus Number
The number of the bus whose voltage is regulated by the control.
Present Regulated Bus Voltage
The present voltage of the regulated bus.
Voltage Error
If the regulated bus' voltage falls outside the regulating range of the transformer (as defined by
the Regulation Minimum Voltage and Regulation Maximum Voltage fields), the Voltage
Error field indicates by how much the voltage deviates from the control range.
Regulation Minimum Voltage
The minimum acceptable voltage at the regulated bus.
Regulation Maximum Voltage
The maximum acceptable voltage at the regulated bus.
Regulation Target Type
As long as the regulated voltage is inside the regulation minimum and maximum, the transformer
will not change its tap ratio. When the regulated voltage moves outside of this regulation range,
Simulator will calculate a new tap ratio in an attempt to bring the regulated voltage back inside
of its range. The Regulation Target Type determines what value is used as a target when
calculating this change in tap ratio. Middle is the default and means that the target is the
average of the regulation minimum and maximum regardless of whether the voltage is high or
low. Max/Min means that the regulation maximum is used as the target when the regulated
voltage is above the maximum, and regulation minimum is used as the target value when the
regulated voltage is below the minimum.
Present Tap Ratio
The tap ratio of the transformer for the current system state.
Minimum Tap Ratio, Maximum Tap Ratio
Minimum and maximum allowable off-nominal tap ratios for the LTC transformer. Typical values
are 0.9 and 1.1.
Tap Step Size
Transformer off-nominal turns ratio increment. The off-nominal turns ratio is either incremented
or decremented from 1.0 in integer multiples of this value. Default value is 0.00625.
Voltage to Tap Sensitivity
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