Approximately optimal tracking control for discrete time-delay systems with disturbances

作者：Tang Gongyou^*; Sun Huiying; Pang Haiping

来源：Progress in Natural Science, 2008, 18(2): 225-231.

DOI：10.1016/j.pnsc.2007.06.008

• discrete systems
• time-delay systems
• disturbances
• optimal control
• tracking control

Optimal tracking control (OTC) for discrete time-delay systems affected by persistent disturbances with quadratic performance index is considered. By introducing a sensitivity parameter, the original OTC problem is transformed into a series of two-point boundary value (TPBV) problems without time-advance or time-delay terms. The obtained OTC law consists of analytic feedforward and feedback terms and a compensation term which is the sum of an infinite series of adjoint vectors. The analytic feedforward and feedback terms can be found by solving a Riccati matrix equation and two Stein matrix equations. The compensation term can be obtained by using an iteration formula of the adjoint vectors. Observers are constructed to make the approximate OTC law physically realizable. A simulation example shows that the approximate approach is effective in tracking the reference input and robust with respect to exogenous persistent disturbances.

• 出版日期2008-2-10
• 单位中国海洋大学; 山东科技大学