Manually Tuning The Control; Current Prop Gain Parameter - Baldor 29M Installation And Operating Manual

Section 1
General Information

Manually Tuning the Control

Current Prop Gain Parameter

MN1230
The next waveform illustrates what happens to the system offset when we apply integral
gain. With the addition of integral gain (2.00 Hz), the system offset is reduced to zero.
Setpoint Command
In some applications the drive cannot be accurately auto-tuned. In these cases it is
necessary to calculate the values needed to tune the drive and manually enter these
calculated parameter values.
This parameter is located in the Level 1, Brushless Control Block. The Current
Prop Gain parameter is normally auto–tuned when motor inductance is not known.
Where auto–tuning can't be used, the proper manual setting for the proportional gain can
be calculated by:
740 x L x A V
Current PROP Gain
Where:
L = Line to neutral inductance of the motor in mH
VAC = Nominal line Volts
A/V = The Amps/Volt scaling of the current feedback
Motor line to neutral inductance can be obtained either from the motor manufacturer or by
measuring the line–to–line inductance and dividing by two.
The A/V scaling for the control can be found in the diagnostic information located in the
DISPLAY MODE.
For most applications setting the Current Prop Gain parameter to a value of 60 will yield
adequate performance.
Process Feedback
VAC
Manually Tuning the Series 29M Control 6-5
Process Gain Settings:
Proportional gain=100
Integral gain=2.00 Hz
(Oscilloscope set to:
vertical=1 V/ division
horizontal=1.0 sec/division