Coevolution-Based Robust Optimal Control for Nonlinear System With Time-Delay Optimal Objectives
针对非线性系统最优控制中优化目标存在时间延迟导致求解困难的问题，提出一种基于协同进化的鲁棒最优控制方法，通过数据驱动估计、协同进化鲁棒优化和自适应时滞控制器提高控制性能，并在时滞非线性系统和生化反应过程中验证了有效性。
Due to its demonstrated efficacy, optimal control has extensive application in nonlinear systems. However, in the optimal control process, the time delays in the optimization objectives makes the optimization problem difficult to solve. To improve the optimal control performance, a coevolution-based robust optimal control (C-TDROC) method is designed. First, a data-driven estimation strategy is proposed to approximate the optimal objectives of nonlinear systems. Then, the approximation errors caused by time delays are described as uncertain representations of system states. Second, a coevolution-based robust optimization (CRO) algorithm is developed to solve the optimal set points of system states. This algorithm generates two coevolutionary particle swarms in robust time delay intervals to improve the robustness of optimal set points. Third, an adaptive time delay controller is proposed for tracking the optimal set points. Then, the Lyapunov-Krasovskii functionals are employed to ensure the stability of C-TDROC. The experiments on a time-delay nonlinear system and a time-delay biochemical reaction process are carried out to prove the availability of C-TDROC.