TRANSIENT RESPONSE BASED ANALYSIS AND PERFORMANCE ASSESSMENT OF DISTURBANCE OBSERVER FOR D.C. MOTOR SPEED CONTROL

D.C. motor speed control systems may be subject to high external disturbances rendering the conventional PID-based feedback control for disturbance rejection unsuitable if implemented alone. In such cases, the use of a disturbance observer (DOB) greatly enhances the performance of the speed control system in terms of efficient rejection of different forms of disturbances. The present work is a simulation-based analysis of a D.C. motor speed control system employing a disturbance observer assisted by a PD controller that adds an additional stability advantage. The performance of the disturbance observer is assessed with and without the PD controller using a time-domain approach via transient response mathematical analysis of the feedback control system.