A cogging torque compensating disturbance estimator for DC motor speed regulation: Design and experimentation

A disturbance estimator was designed and integrated into an existing proportional and integral controller DC motor speed control system to improve the speed regulation. The DC motor in the existing control system possessed a large amount of cogging torque, causing a periodic speed error. This cogging torque was treated as an equivalent input disturbance which then was estimated using a disturbance estimator. The estimated disturbance was utilized to reject the cogging torque. The speed response was largely improved by augmenting this disturbance estimator. The robust stability and performance of this scheme were investigated. Experiment results demonstrated the effectiveness of this scheme.