Anti-windup design for PI-type speed controller based on nonlinear compensation and disturbance suppression

In order to solve the problem of dynamic quality deterioration caused by the proportional plus integral (PI) integral saturation of speed regulator in permanent magnet synchronous motor servo system, a novel anti-windup(AW) design was proposed. Uncertainties in the mode were regarded as a disturbance of the system by the AW method firstly. Then in order to improve the system low performance and disturbance rejection property a compound control method, which combined model-based friction compensation with disturbance observer compensation, was designed for speed loop based on PI control strategy. Finally, the desaturation system response of re-entering the PI mode from proportional (P) mode was used as a system response with an initial value, and the error and integral value condition which ensured the system non-overshoot were derived using dynamic responses of the system error equation in time-domain. When the system was saturated, it ran at maximum acceleration. Until the condition was satisfied, the PI mode was re-entered and an initial value was assigned to the integrator. The results show that this method ensures the desaturation system excellent dynamic performance and non-overshoot operation. Compared with the existing conditional integration and its improved methods, the simulated and experimental results demonstrate the feasibility and advantage of the new AW design. © 2015, Central South University of Technology. All right reserved.