Rockwell Automation 20Y PowerFlex Active Front End - Manual (Page 153)

Rockwell Automation Publication 20Y-UM001E-EN-P - July 2014 153
Application Notes Appendix C
Voltage Boost
AFE parameter 61 [DC Volt Ref ] can be adjusted to boost the DC voltage.
The maximum value of parameter 61 [DC Volt Ref ] is:
[Rated Volts] x 1.35 x 1.3 for 400/480V units
[Rated Volts] x 1.35 x 1.15 for 600/690V units,
where [Rated Volts] is the AC input voltage for the AFE.
The maximum AC output to the motor = [DC Volt Ref ] / (
√ 2 x 1.1)
Example:
AC line voltage = 400V AC
Motor = 460V AC
Max [DC Volt Ref ] = 400 x 1.35 x 1.3 = 702V DC
Maximum AC output to motor = 702V DC / (
√ 2 x 1.1) = 451V AC
In addition, the AC input current required by the AFE increases when using
voltage boost. Both the continuous and overload AC input current ratings must
not be exceeded or the AFE will trip on overload. See the
Advanced Procedure to
Size the AFE on page 152 for sizing guidelines.
ATTENTION: The AFE can be used for voltage boost but cannot be used to lower
the DC bus voltage. The minimum DC bus voltage is limited by the rectified diode
bridge voltage.