论文标题
分布式和局部模型预测控制。第二部分:理论保证
Distributed and Localized Model Predictive Control. Part II: Theoretical Guarantees
论文作者
论文摘要
工程的网络物理系统正在越来越大且复杂。这些系统需要可扩展的控制器,在存在加性噪声的情况下,可牢固满足状态和输入约束 - 此类控制器也应伴随于可行性和稳定性的理论保证。在我们的同伴论文中,我们为大规模线性系统引入了分布式和局部模型预测控制(DLMPC)。 DLMPC是一种可扩展的闭环MPC方案,在该方案中,子系统仅需要交换本地信息才能合成和实现本地控制器。在本文中,我们为DLMPC提供了递归的可行性和渐近稳定性保证。我们利用系统级综合框架来表达闭环系统及其相应的Lyapunov功能的最大正稳定性设置,均以闭环系统的响应来表达。我们将不变式设置用作DLMPC的终端集,并表明这可以保证具有最小保守主义的可行性。我们将Lyapunov功能用作终端成本,并表明这可以保证稳定性。我们提供了完全分布的局部算法来离线计算终端集,并为在线DLMPC算法提供必要的添加,以适应耦合的终端约束和成本。在所有算法中,仅需要局部信息交换,并且计算复杂性与全球系统大小无关 - 我们在分析和实验上证明了这一点。这是第一种分布式MPC方法,可为名义和健壮设置提供最小保守但完全分布的保证,以提供递归可行性和渐近稳定性。
Engineered cyberphysical systems are growing increasingly large and complex. These systems require scalable controllers that robustly satisfy state and input constraints in the presence of additive noise -- such controllers should also be accompanied by theoretical guarantees on feasibility and stability. In our companion paper, we introduced Distributed and Localized Model Predictive Control (DLMPC) for large-scale linear systems; DLMPC is a scalable closed-loop MPC scheme in which subsystems need only exchange local information in order to synthesize and implement local controllers. In this paper, we provide recursive feasibility and asymptotic stability guarantees for DLMPC. We leverage the System Level Synthesis framework to express the maximal positive robust invariant set for the closed-loop system and its corresponding Lyapunov function, both in terms of the closed-loop system responses. We use the invariant set as the terminal set for DLMPC, and show that this guarantees feasibility with minimal conservatism. We use the Lyapunov function as the terminal cost, and show that this guarantees stability. We provide fully distributed and localized algorithms to compute the terminal set offline, and also provide necessary additions to the online DLMPC algorithm to accommodate coupled terminal constraint and cost. In all algorithms, only local information exchanges are necessary, and computational complexity is independent of the global system size -- we demonstrate this analytically and experimentally. This is the first distributed MPC approach that provides minimally conservative yet fully distributed guarantees for recursive feasibility and asymptotic stability, for both nominal and robust settings.