An algebraic and suboptimal solution of constrained model predictive control via tangent hyperbolic function

Dursun U., Tascikaraoglu F. Y., Üstoğlu İ.

ASIAN JOURNAL OF CONTROL, cilt.23, sa.5, ss.2420-2430, 2021 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 23 Sayı: 5
  • Basım Tarihi: 2021
  • Doi Numarası: 10.1002/asjc.2357
  • Dergi Adı: ASIAN JOURNAL OF CONTROL
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Applied Science & Technology Source, Compendex, INSPEC, zbMATH
  • Sayfa Sayıları: ss.2420-2430
  • Anahtar Kelimeler: Constrained Optimal Control, Input Constraint, Model Predictive Control, Saturation-like Function, State Constraint, Tangent Hyperbolic
  • İstanbul Teknik Üniversitesi Adresli: Evet

Özet

In this paper, we propose a novel method to solve the model predictive control (MPC) problem for linear time-invariant (LTI) systems with input and output constraints. We establish an algebraic control rule to solve the MPC problem to overcome the computational time of online optimization methods. For this purpose, we express system constraints as a continuous function through the tangent-hyperbolic function, hence the optimization problem is reformulated. There are two steps for the solution of the optimization problem. In the first step, the optimal control signal is determined by the use of the necessary condition for optimality, assuming that there is only input constraint. In the latter, the solution obtained in the first step is revised to keep the system states in a feasible region. It is shown that the solution is suboptimal. The proposed solution method is simulated for three different sample systems, and the results are compared with the classical MPC, which show that the new algebraic method dramatically reduces the computational time of MPC.