User Guide

AN1292 Tuning Guide
2010 Microchip Technology Inc. DS70640A-page 7
PI Current Controllers
Some general guidelines for effective tuning of this application’s PI controllers
are:
- Both controllers, on the D and Q axis, will have the same values for corre-
sponding Proportional (D_CURRCNTR_PTERM, Q_CURRCNTR_PTERM),
Integral (D_CURRCNTR_ITERM, Q_CURRCNTR_ITERM),
Anti-windup Compensation (D_CURRCNTR_CTERM, Q_CURRCNTR_ITERM),
and Minimum-Maximum (D_CURRCNTR_OUTMAX, Q_CURRCNTR_OUTMAX,
D_CURRCNTR_OUTMIN, Q_CURRCNTR_OUTMIN) terms.
- In general, whenever current oscillation happens, lower the proportional
gain term making sure integral gain is from 5 to 10 times smaller than
proportional gain.
Use the values shown below as a starting point.
userparms.h
c) Open Loop Parameters Optimization
The settings above would enable open loop operation. Once it has been verified
that everything is working fine with the setup previously explained, try to fine tune
the parameters for smoother and more efficient operation by:
decreasing startup torque current
increasing speedup ramp rate
reducing the lock time
decreasing end speed