A novel piecewise Anti-Windup design for speed loop PI controller of PMSM servo system

A novel PI Controller Anti-Windup(AW) design which is based on the way of back-calculate is presented. It is to put forward the principle for the tuning of back-calculation gain, which needs to be changed along with the step command in order get a optimal dynamic response. The proposed AW design can avoid the problem caused by the fixed back-calculation gain in the classical AW design, and prevent saturation withdrawing ahead of time or a unexpected large overshoot due to a larger or smaller back-calculation gain respectively. The new method of AW is compared with the classical AW design by simulation and experiment on application platform of permanent magnet synchronous motor (PMSM) servo system. A PI controller with the proposed AW design can decrease the overshoot with shortening the settling time of system step-response, which can be observed obviously in wide dynamic variation. It reduced the difficulty of the tuning of the controller parameters.