In this paper, the nonlinear robust reference tracking problem is considered and an Improved Two‐Loop Nonlinear Model Predictive Control (ITL‐NMPC) design is proposed for a pre‐controlled system with bounded uncertainties subject to input and state constraints. In the industry, this scheme leads the lower design cost and fewer implementation risks since (i) it allows the existing controller to remain unchanged without any manipulation, (ii) it does not need the open‐loop model of the pre‐controlled system, and (iii) it does not require the terminal cost and constraint definition. For the proposed ITL‐NMPC, a practical parameter tuning algorithm is introduced and its robust exponential stability, as well as recursive feasibility, are guaranteed. Simulation results are used to better illustrate the effectiveness of the proposed approach and show that the proposed method not only improves the control performance of the pre‐controlled system but also reduces the design cost while satisfying the constraints.

中文翻译：

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具有实用优势的非线性鲁棒参考跟踪的改进的两环模型预测控制设计

在本文中，考虑了非线性鲁棒参考跟踪问题，并针对带有输入和状态约束的不确定不确定性的预控制系统，提出了一种改进的两回路非线性模型预测控制（ITL-NMPC）设计。在业界，此方案可带来更低的设计成本和更低的实施风险，因为（i）它可以使现有控制器保持不变而无需任何操作；（ii）它不需要预控制系统的开环模型， （iii）不需要终端成本和约束条件定义。对于提出的ITL-NMPC，引入了一种实用的参数调整算法，并保证了其鲁棒的指数稳定性以及递归的可行性。