Rockwell Automation 20G PowerFlex 750-Series AC Drives - Manual (Page 19)

Rockwell Automation Publication 750-RM002B-EN-P - September 2013 19
Drive Configuration Chapter 1
Refer to the PowerFlex 750-Series Programming Manual, publication 750-
PM001 , for parameter descriptions and defaults.
When using sine wave or dv/dt filters, the PWM frequency must match the filter
design. The drive’s thermal protection changes the PWM frequency if over
temperature conditions are detected. Set P420 [Drive OL Mode] to option 1
“Reduce CLmt” and P38 [PWM Frequency] to the filter instructions.
Additional Parameter Changes
When using adjustable voltage control it is necessary to change additional
parameters beyond the feature itself. Use this table to assist in setting these
parameters.
Table 2 - Adjustable Voltage Applications Parameter Settings
1141 Adj Vltg DecTime n Secs Application dependent
1142 Adj Vltg Preset1 n VAC Application dependent
1153 Dead Time Comp n % Vary from 0% to 100%. Dead Time Comp is best set
to 0% when output of the Sine wave Filter is fed
into a transformer, to prevent or minimize DC Offset
voltages.
Parameter No. Parameter Name Setting Description
38 PWM Frequency 2 kHz or 4 kHz Match the setting with filter tuning.
40 Mtr Options Cfg Bit 5 = 0 Reflected wave is turned off so that there are no
missing pulses in the output voltage waveform and
to minimize any offsets that can appear.
Bit 8 = 1 AsyncPWMLock is on because the filter is tuned to
the carrier frequency. The carrier frequency must be
fixed, if it changes the filter will not work. Also, set
the PWM frequency match filter tuning, either 2 kHz
or 4 kHz.
Bit 9 = 1 PWM Freq Lock is on because the filter is tuned to
the carrier frequency. The carrier frequency must be
fixed, if it changes the filter will not work. Also, set
the PWM frequency match filter tuning, either 2 kHz
or 4 kHz.
Bit 11 = 0 The “Elect Stab” bit affects angle stability and
voltage stability.
Angle stability gain is set for 0 so it does not
compensate for the current going into the filter’s
caps. Voltage stability gain is set for 0 for the same
reason.
Bit 12 = 0 Transistor diagnostics is turned off because that
sequence of turning transistors on and off charges
the caps in the filter and can cause an IOC trip.
43 Flux Up Enable 0 Leave at the “Manual” setting.
44 Flux Up Time Default Leave at 0.0000 seconds.
Parameter No. Parameter Name Setting Description