Stabilization of motion control system with rate limiter using linear reference model

Abstract

Actuator rate saturation has characteristics to increase the phase lag of the system and it can be one of the factors that destabilize the motion control system for a higher control response. We propose a new control method that can stabilize the system with rate limited actuators. First, it is shown that the actuator rate limited characteristics causes control systems to be unstable using both describing function analysis and nonlinear simulations. Next, the proposed method using linear actuator reference model is described. It can avoid the rate saturation of actuators to improve the phase lag characteristics. Then, the effectiveness of proposed method is demonstrated through stability analysis and nonlinear simulations.