Study of anti-windup pi controllers with different coupling–decoupling tuning gains in motor speed

Proportional-integral (PI) controller is still a widely used closed-loop controller in industrial applications due to its simplicity. PI controllers experience difficulty in having both non-overshoot with short rise time. Such unfavorable response is due to its coupled tuning-gains and the integral windup, which eventually leads to system instability. Various anti-windup techniques have been proposed. However, similar to the conventional PI controllers, most of these techniques have coupled proportional and integral tuning gains that affect one another. The controllers contain adaptive switching between the conventional and its designated integral control depending on the saturation state. This paper proposes a robust non-switching anti-windup PI controller with semi-decoupling tuning gain. Speed control simulation and experimental testing are conducted to investigate the impact of the various tuning gain dependency. The proposed controller shows a fast response with no overshoot as compared to the conventional and other non-switching anti-windup PI controllers with coupling and decoupling tuning gain at certain loading conditions.