面向集中式控制的微电网信息物理系统分层建模方法

The Hierarchical Modeling Approach for Centralized Control Microgrid Cyber Physical System

为清晰展示微电网各单元的运行状态及其状态转移过程,提出一种含物理设备层、控制决策层和系统优化层的3层信息物理融合建模框架,对3个层级的功能进行设计,分别建立各层级的模型:采用状态机描述物理设备层各单元不同运行状态间的转换过程,在每个状态下各单元连续变化特性由微分方程表征;采用多元组的形式化数学表达式描述控制决策层的控制功能;基于系统的实际需求建立系统优化层的优化目标,用于确定优化微电网系统的优化运行策略。3层模型的组合形成了信息物理融合的微电网系统整体模型,用于呈现微电网系统在某一优化目标下的运行控制过程中各个单元的状态转移过程。最后以一个典型的交直流混合微电网系统为例对所提的建模方法进行验证,结果表明,所提建模方法有效地提高了微电网系统的可观性。

To clearly show the operation state of each unit of the microgrid and its state transfer process, a three-layer cyber-physical integration modeling framework containing physical device layer, control decision layer and system optimization layer was proposed. Based on the design of the functions of the three layers, the model of each layer was established respectively. The state machine was used to describe the transition process between different operating states of each unit in the physical device layer, and the continuous change characteristics of each unit in each state were characterized by differential equations. The formal mathematical expressions of multi-element tuple were used to describe the control functions of the control decision layer. The optimization objectives of the microgrid system layer were established based on the actual requirements of the system, and can be used to determine the optimal operation strategy of the microgrid system. The combination of the three layers of models can form an overall model of the microgrid system with cyber-physical integration, for the purpose of presenting the state transition process of each unit in the operation and control process of the microgrid system under a certain optimization objective. Finally, a typical hybrid AC/DC microgrid system was taken as an example to verify the proposed modeling approach, and the results show that the proposed modeling approach effectively improves the observability of the microgrid system.