Active Damped PI Speed Loop Design for Motor Direct-Drive Operating Mechanism for High-Voltage Circuit Breakers

To address the prevalent issues of oscillation and overshoot in high-voltage circuit breaker motor direct-drive mechanisms under classical PI control, this paper proposes an optimized PI speed loop with active damping characteristics. By first establishing a detailed kinematic and dynamic model of the mechanism, we reveal the inherent coupling between tracking performance, disturbance immunity, and the damping ratio within the classical PI speed loop. Our novel method introduces a speed feedback channel at the output of the PI controller to synthesize equivalent viscous damping, thereby enhancing system stability without compromising responsiveness. Through rigorous simulation and experimental validation, the proposed controller’s effectiveness is demonstrated. Compared with the traditional PI controller, the ADPI method reduces the velocity overshoot to only 5.76% in the startup phase, and the maximum velocity tracking error of the velocity is only 18.62% and the cumulative position tracking error is only 0.632 rad under the actual working condition, which is a reduction of 42.7% in the positional error relative to the traditional PI method. The controller also exhibits low sensitivity to changes in the system’s equivalent rotational inertia. This work provides a low-complexity and easy-to-implement speed loop performance enhancement scheme, ideally suited for the short-duration, high-dynamic-load conditions of high-voltage circuit breaker applications.