title: On oscillation reduction in feedback control for processes with an uncertain dead time and internal-external disturbances.
abstract: This paper aims to find a practical solution to reduce oscillation on the Smith Predictor (SP) based design with the dead time (DT) uncertainty, making it less sensitive to DT change and more effective in disturbance rejection. First, a conditional feedback mechanism is introduced in SP to reduce the amount of oscillation caused by the model inaccuracies in the DT parameter. Then, to address the oscillation caused by the phase lag in traditional PI controller and uncertain dynamics, this conditional SP is combined with active disturbance rejection control (ADRC), assisted by the knowledge of process dynamics. A practical tuning method is provided for the practicing engineers. The proposed approach is validated in extensive simulation studies with different types of plants and in frequency domain analysis. The simulation results show significant improvements in performance robustness and transient response.
authors.affiliation: State Key Lab of Power Systems, Department of Thermal Engineering, Tsinghua University, Haidian, Beijing 100084, China. Electronic address: zhangyuqiong10@mails.tsinghua.edu.cn.
authors.forename: Yuqiong
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: State Key Lab of Power Systems, Department of Thermal Engineering, Tsinghua University, Haidian, Beijing 100084, China. Electronic address: lidongh@mail.tsinghua.edu.cn.
authors.forename: Donghai
authors.initials: D
authors.lastname: Li
authors.affiliation: Center for Advanced Control Technologies, Cleveland State University, Cleveland, OH 4415, United States. Electronic address: z.gao@ieee.org.
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Gao
authors.affiliation: Center for Advanced Control Technologies, Cleveland State University, Cleveland, OH 4415, United States. Electronic address: qinlingzheng@gmail.com.
authors.forename: Qinling
authors.initials: Q
authors.lastname: Zheng
mesh_terms: D000465:Algorithms; D003198:Computer Simulation; D004738:Engineering; D004867:Equipment Design; D005246:Feedback; D007221:Industry; D009010:Monte Carlo Method; D015203:Reproducibility of Results; D035501:Uncertainty
keywords: Active disturbance rejection control; Dead time; Model mismatch; Smith Predictor