Rockwell Automation 20D PowerFlex 700S with Phase I Control Reference Manual - Manual (Page 129)

Rockwell Automation Publication PFLEX-RM002D-EN-E - August 2013 129
Detail Drive Configuration and Operation Chapter 1
d. Parameter 95 [SregOut FiltGain] and parameter 93 [SRegFB Filt Gain]
= 0.5;
Parameter 94 [SReg FB Filt BW] and parameter 96 [SregOut Filt BW]
= 20
7. If gear noise or chatter is still present after turning on the filters, repeat
steps 2 through 6 with a lower speed regulator BW (parameter 90 [Spd
Reg BW]).
8. If the desired bandwidth cannot be achieved due to gear noise or chatter,
follow the procedure for Advanced Tuning for the Speed Regulator with
Gearbox or Belt below.
Advanced Tuning for the Speed Regulator with Gearbox or Belt
When using a system with a gearbox or belts, the backlash or lost motion can
cause instability. The inertia adaptation feature can be used to alleviate this
instability. Follow the steps below to use inertia adaptation:
1. Identify motor and system inertia (in seconds).
The motor inertia can be determined by performing an inertia test with
the motor uncoupled from the load, or the motor inertia in seconds can be
calculated using the following formula:
where WK2 is the inertia in lbft2, RPM is the base motor speed of the
motor, and Tacc is the rated torque of the motor in lb
• ft. Tacc can be
calculated by the following:
where HP is the nameplate horsepower of the motor and RPM is the base
motor speed of the motor.
System Inertia (parameter 9 [Total Inertia]) is determined by performing
the inertia test with the load coupled, or the value (in seconds) can be
calculated using the formulas above if WK2 is known for the system.