| Title |
Stability Analysis on a PI Observer-Based Position Control System Using a Reduced DC Motor Model |
| Authors |
김도훈(Doe Hun Kim) ; 아마레 네비옐레울 다니엘(Nebiyeleul Daniel Amare) ; 손영익(Young Ik Son) |
| DOI |
https://doi.org/10.5370/KIEE.2020.69.12.1935 |
| Keywords |
Motor position control; Reduced model; PI observer; Disturbance observer; System stability |
| Abstract |
When designing position controllers for DC motors, it is convenient to use a reduced-order model omitting the fast electric dynamics of the system. In order to compensate for the effects of both structured and unstructured model uncertainties, PI (Proportional Integral) observers have been widely adopted for disturbance observer-based controllers. In general, the disturbance estimation performance of the observer can be arbitrarily adjusted using the observer gains. However, the stability of the closed-loop system becomes compromised at higher controller and observer gains when using an observer-based control system designed based on a reduced-order model. This paper proposes a reduced-order PI observer-based back-stepping position controller for a DC motor designed based on a reduced-order model. A boundary of the controller and observer gains is presented by using Routh-Hurwitz stability test in which the closed loop stability is maintained. A computer simulation confirms that the closed-loop system is stable under the presented conditions and proposed scheme. |