Fixed Time Sliding Mode Tracking Control of Permanent Magnet Synchronous Motor under Mismatched Disturbances
To solve the problem of rotational speed tracking of permanent magnet synchronous motor(PMSM)with mismatched dis-turbances,a fixed-time sliding mode tracking control based on super-twisted disturbance observer is proposed.Firstly,the improved disturbance observer is based on the super-twisted theory,so that the observer can observe the matched and unmatched perturbations in a finite time.Then,the fixed-time approach law is introduced to make the system reach the sliding mode surface in a fixed time and improve the tracking accuracy.Then,the mismatched disturbances and feedback current are introduced into the sliding mode surface,so that the tracking error converges to the sliding mode surface in a fixed time.Moreover,the rotation tracking and current control of the PMSM are realized.Finally,taking PMSM as an example,it is verified that the method has higher tracking accuracy and can suppress the influence of the bad factors such as mismatched disturbances by comparing with integral sliding mode control and non-singular terminal sliding mode control.
permanent magnet synchronous motorsliding mode controlmismatched disturbancesuper-twisted theory