Performance improvement of saturated system using loop shaping approach

Abstract

Actuator saturation is an important issue when designing practical control systems. It usually induces the windup phenomenon and even yields system instability. In this paper, a two-stage controller design method is proposed for systems with actuator limitations using the loop shaping approach. In this approach, a pre-designed controller is first used to stabilize the control system to achieve the desired performance. A loop-shaping-based auxiliary controller is then introduced to reduce the windup effect, which might be caused by actuator limitation or functional damage during the mission.

A new anti‐windup strategy for PID controllers with derivative filters

“…For the error dynamic as given as (11) and the PID controller in (4), the solution of the optimal H ∞ problem described in (13) For the error dynamic as given as (11) and the PID controller in (4), the solution of the optimal H ∞ problem described in (13) …”

“…From (11), it is known that the value of G e (s) ∞ will not be less than L. Besides, it is easy to be calculated that when choose m 1 = 0 and m 2 = 1/L, then G e (s) becomes From Theorem 1, the auxiliary compensator gain M is obtained and the resulting PID AW controller can be easily implemented in the form shown in Fig. To calculate G e (s) ∞ , it is first assumed that m 1 and m 2 are chosen such that G e (s) is stable.…”

“…The widespread deployment of PID controllers stems primarily from their simple architectures, low cost and effectiveness in use. Many schemes have been proposed for resolving this "windup" problem, including the classical anti-windup (AW) scheme [7], the conventional AW scheme [8], the conditioning technique [9], and the observer-based method [10,11]. However, PID controllers suffer a major drawback in that when the controller output signal saturates, the controlled system is unable to reach the specified set Manuscript received February 24, 2010; revised June 26, 2010; accepted August 16, 2010. The author is with the Department of Automation and Control Engineering, Far-East University, No.…”

“…As a result, oscillations are induced, which cause serious performance deterioration and may even prompt the onset of system instability. Many schemes have been proposed for resolving this "windup" problem, including the classical anti-windup (AW) scheme [7], the conventional AW scheme [8], the conditioning technique [9], and the observer-based method [10,11]. Such methods generally adopt a two-step approach in resolving the windup problem.…”

Best Tracking Performance of Networked Control Systems Based on Communication Constraints

“…The networked induced-delay and data losses seriously affected the performance of control systems. The technologies regarding modeling of the networked control systems and stabilization analysis are now fairly mature [1][2][3][4][5][6][7][8][9][10], but considering only the angle of application to the stability of the system is not enough; also one should consider the performance of system. This paper mainly focuses on solving new problems with communication networks, such as the best tracking performance of networked control systems.…”