Optimal V-Plane Robust Stabilization Method for Interval Uncertain Fractional Order PID Control Systems

• Published in: Fractal and fractional Vol. 5; no. 1; p. 3
• Main Authors: Tufenkci, Sevilay, Senol, Bilal, Matušů, Radek, Alagoz, Baris Baykant
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.03.2021
• Subjects: Algorithms; computer-aided control design; Control stability; Control systems; Control theory; Controllers; Design specifications; Heuristic; Methods; Optimization; Particle swarm optimization; Polynomials; Proportional integral derivative; Robust control; Robust stabilization; stability of linear systems; System effectiveness; Systems design; Systems stability; Tuning; uncertain systems
• ISSN: 2504-3110; 2504-3110
• DOI: 10.3390/fractalfract5010003

Robust stability is a major concern for real-world control applications. Realization of optimal robust stability requires a stabilization scheme, which ensures that the control system is stable and presents robust performance for a predefined range of system perturbations. This study presented an optimal robust stabilization approach for closed-loop fractional order proportional integral derivative (FOPID) control systems with interval parametric uncertainty and uncertain time delay. This stabilization approach, which is carried out in a v-plane, relies on the placement of the minimum angle system pole to a predefined target angle within the stability region of the first Riemann sheet. For this purpose, tuning of FOPID controller coefficients was performed to minimize a root angle error that is defined as the squared difference of minimum angle root of interval characteristic polynomials and the desired target angle within the stability region of the v-plane. To solve this optimization problem, a particle swarm optimization (PSO) algorithm was implemented. Findings of the study reveal that tuning of the target angle can also be used to improve the robust control performance of interval uncertain FOPID control systems. Illustrative examples demonstrated the effectiveness of the proposed v-domain, optimal, robust stabilization of FOPID control systems.