In this paper,a data-based scheme is proposed to solve the optimal tracking problem of autonomous nonlinear switching systems.The system state is forced to track the reference signal by minimizing the performance func...In this paper,a data-based scheme is proposed to solve the optimal tracking problem of autonomous nonlinear switching systems.The system state is forced to track the reference signal by minimizing the performance function.First,the problem is transformed to solve the corresponding Bellman optimality equation in terms of the Q-function(also named as action value function).Then,an iterative algorithm based on adaptive dynamic programming(ADP)is developed to find the optimal solution which is totally based on sampled data.The linear-in-parameter(LIP)neural network is taken as the value function approximator.Considering the presence of approximation error at each iteration step,the generated approximated value function sequence is proved to be boundedness around the exact optimal solution under some verifiable assumptions.Moreover,the effect that the learning process will be terminated after a finite number of iterations is investigated in this paper.A sufficient condition for asymptotically stability of the tracking error is derived.Finally,the effectiveness of the algorithm is demonstrated with three simulation examples.展开更多
Sampled-data (SD) based linear quadratic (LQ) control problem of stochastic linear continuous-time (LCT) systems is discussed. Two types of systems are involved. One is time-invariant and the other is time-varying. In...Sampled-data (SD) based linear quadratic (LQ) control problem of stochastic linear continuous-time (LCT) systems is discussed. Two types of systems are involved. One is time-invariant and the other is time-varying. In addition to stability analysis of the closed-loop systems, the index difference between SD-based LQ control and conventional LQ control is investigated. It is shown that when sample time ?T is small, so is the index difference. In addition, the upper bounds of the differences are also presented, which are O(?T2) and O(?T), respectively.展开更多
随着电力系统数据采集手段的不断完善,基于数据的分析方法在电力系统运行分析中扮演着日益重要的角色。现有的数据分析方法主要分析数据之间的相关关系。事实上,两个强相关变量间通常呈现出不对称的因果关系。若能揭示电力系统运行变量...随着电力系统数据采集手段的不断完善,基于数据的分析方法在电力系统运行分析中扮演着日益重要的角色。现有的数据分析方法主要分析数据之间的相关关系。事实上,两个强相关变量间通常呈现出不对称的因果关系。若能揭示电力系统运行变量间的因果关系,必将有助于深刻地洞察电力系统运行的内在规律性。近年来,因果推断的研究取得很大进展,使得基于数据的因果分析成为可能。该文从物理机制上揭示电力系统中强相关变量之间因果关系的不对称属性;提出一种逆信息熵因果推理(reciprocal information entropy causal inference,RIECI)方法,所构建的指标不仅可以有效判别相关变量间的因果方向,还能正确反映因果强度。在电力系统算例中的验证表明,RIECI方法能有效揭示电力系统运行数据中的因果关系。对电力系统运行数据中因果关系的分析对于认知电力系统运行机理和正确调控电力系统运行状态有重要意义。展开更多
基金supported by the National Natural Science Foundation of China(61921004,U1713209,61803085,and 62041301)。
文摘In this paper,a data-based scheme is proposed to solve the optimal tracking problem of autonomous nonlinear switching systems.The system state is forced to track the reference signal by minimizing the performance function.First,the problem is transformed to solve the corresponding Bellman optimality equation in terms of the Q-function(also named as action value function).Then,an iterative algorithm based on adaptive dynamic programming(ADP)is developed to find the optimal solution which is totally based on sampled data.The linear-in-parameter(LIP)neural network is taken as the value function approximator.Considering the presence of approximation error at each iteration step,the generated approximated value function sequence is proved to be boundedness around the exact optimal solution under some verifiable assumptions.Moreover,the effect that the learning process will be terminated after a finite number of iterations is investigated in this paper.A sufficient condition for asymptotically stability of the tracking error is derived.Finally,the effectiveness of the algorithm is demonstrated with three simulation examples.
基金This work was supported by the National Natural Science Foundation of China.
文摘Sampled-data (SD) based linear quadratic (LQ) control problem of stochastic linear continuous-time (LCT) systems is discussed. Two types of systems are involved. One is time-invariant and the other is time-varying. In addition to stability analysis of the closed-loop systems, the index difference between SD-based LQ control and conventional LQ control is investigated. It is shown that when sample time ?T is small, so is the index difference. In addition, the upper bounds of the differences are also presented, which are O(?T2) and O(?T), respectively.
文摘随着电力系统数据采集手段的不断完善,基于数据的分析方法在电力系统运行分析中扮演着日益重要的角色。现有的数据分析方法主要分析数据之间的相关关系。事实上,两个强相关变量间通常呈现出不对称的因果关系。若能揭示电力系统运行变量间的因果关系,必将有助于深刻地洞察电力系统运行的内在规律性。近年来,因果推断的研究取得很大进展,使得基于数据的因果分析成为可能。该文从物理机制上揭示电力系统中强相关变量之间因果关系的不对称属性;提出一种逆信息熵因果推理(reciprocal information entropy causal inference,RIECI)方法,所构建的指标不仅可以有效判别相关变量间的因果方向,还能正确反映因果强度。在电力系统算例中的验证表明,RIECI方法能有效揭示电力系统运行数据中的因果关系。对电力系统运行数据中因果关系的分析对于认知电力系统运行机理和正确调控电力系统运行状态有重要意义。