信息物理融合视角下的电流纵差保护可靠性分析

现代电网已经具备信息-物理紧密融合的特征,电流差动保护是信息物理紧密耦合的典型应用,因此,有必要从信息物理融合的视角研究其可靠性。从物理-量测-通信-决策的完整闭环控制过程出发,分析线路电流、互感器测量误差、通信延时及保护判据(分析决策)等信息物理因素对电流差动保护的综合影响,提出电力信息物理系统视角下电流差动保护业务的误动概率模型。然后,通过仿真算例验证了模型的合理性,并分析了影响电流差动保护误动的关键因素。

Reliability Analysis of the Current Differential Protection with Integration of Cyber and Physical System

Modern power system is developing into a cyber physical power system (CPPS). The current differential protection is a typical application with ICT and physical function tightly coupled. So it is necessary to study its reliability from the perspective of CPPS. On the basis of the closed-loop control process of physical-measurement-communication-decision making, the paper analyzes the integrated effects of cyber and physical factors, such as line current, measurement error of CT, communication delay and protection criteria, on the current differential protection, and proposes the mis-operation probability model of the current differential protection. On that basis, a simulation is performed to verify the model, and the key factors affecting the reliability are analyzed.