User guide

Xenus Plus User Guide Operational Theory
Copley Controls 20
Current Loop Gains
The current loop uses these gains:
Gain
Description
Cp - Current loop proportional
The current error (the difference between the actual and the limited commanded
current) is multiplied by this value. The primary effect of this gain is to increase
bandwidth (or decrease the step-response time) as the gain is increased.
Ci - Current loop integral
The integral of the current error is multiplied by this value. Integral gain reduces the
current error to zero over time. It controls the DC accuracy of the loop, or the
flatness of the top of a square wave signal. The error integral is the accumulated
sum of the current error value over time.
Current Loop Output
The output of the current loop is a command that sets the duty cycle of the PWM output stage of
the drive.
Auto Tune
CME 2 provides a current loop Auto Tune feature, which automatically determines optimal Cp and
Ci values for the motor. For more information, see the CME 2 User Guide.