基于层次结构模型的电力CPS安全评估

发布时间：2018-04-24 21:47

本文选题：电力CPS + 层次结构模型　；参考：《武汉大学》2017年硕士论文

【摘要】：由于智能电网的大力发展,信息系统在电力系统运行中扮演着越来越重要的角色。传统的电力系统已经转变成了信息系统与电力系统紧密协作的电力信息-物理融合系统(Cyber-physical System,CPS)。电力CPS中信息技术的广泛应用为电力生产和管理带来便利的同时,也引入了新的安全威胁。近年来,由信息系统故障引发的电网波动甚至大规模停电事件不断出现,电力CPS的安全性问题日益突出。电力CPS安全评估是对系统威胁、脆弱性等的综合评估,有利于找出系统薄弱环节并制定相应改进方案,对当前电网的可靠运行与未来能源系统的架构设计有着重要的指导意义。现有的评估模型局限于单一空间安全,没有将电力CPS当作一个有机整体进行评估。基于以上背景,本文主要对电力CPS的建模方法、电力CPS层次体系下的风险及其跨空间传播,以及电力CPS的安全评估问题进行了研究。在层次结构模型下,从静态的电力CPS信息设备节点风险到动态电力CPS连锁故障,对电力CPS安全风险进行了全面的分析。具体研究内容包括以下几个方面:(1)研究面向对象的电力CPS层次体系结构模型。首先分析了电力CPS以能量流-信息流的方式进行信息-物理的交互,然后针对电力CPS离散与连续系统耦合的特点,提出了面向对象的层次化建模方法与结构模型。该模型将电力CPS划分为信息设备层、通信子网层、网络层、信息业务层和物理系统层5个层次,采用面向对象的方法定义了各个层次的关系及构成,提高了对电力CPS进行分析、评估和仿真的可行性。(2)层次结构下的电力CPS信息系统故障与风险因素分析。分析了电力CPS风险的来源,然后基于面向对象的层次结构,分别从信息设备层、通信子网层、网络层、信息业务层和物理系统层5个层次对电力CPS的故障与风险因素进行分析。最后,对信息系统故障进行了分类。对电力CPS的风险进行解构,明确了信息系统故障的来源,有利于故障的分析与防护。(3)研究基于层次结构模型的电力CPS信息设备故障风险评估方法。首先建立电力CPS信息系统在层次结构体系中的耦合模型。然后以一种基于层次分析法(AHP)的评估算法作为耦合模型输出函数,选取评估指标作为模型的输入,信息设备故障风险为模型输出。该模型考虑了信息系统内部以及信息系统与电力系统之间的静态关联关系,可以对电力CPS信息系统风险进行静态评估。最后选取D2-1型变电站作为算例进行设备故障风险评估,评估结果与实际情况相符,从而验证了该方法的有效性。(4)研究电力CPS中信息系统安全风险的跨空间传播机制以及基于改进攻击图的安全风险评估。首先,在分析电力CPS中信息系统风险的基础上,阐述了电力CPS风险跨空间传播的基本方式。然后,根据改进攻击图建立了电力CPS安全风险传播模型,以信息设备、电力业务、电力系统故障为节点,建立风险传播路径,通过改进攻击图定量计算节点和攻击路径对于信息设备故障传播的灵敏度。最后,综合故障风险评估与灵敏度的结果,对电力CPS进行考虑动态时序的综合安全评估。
[Abstract]:Because of the development of smart grid, the information system plays a more and more important role in the operation of the power system. The traditional power system has changed into the Cyber-physical System (CPS). The wide application of the information technology in the power CPS is the electric power production. With the convenience of management, new security threats have also been introduced. In recent years, the power grid fluctuation and even large-scale blackout caused by the information system failure are appearing continuously. The security problem of the power CPS is becoming more and more prominent. The power CPS security assessment is a comprehensive assessment of the system threat and vulnerability, which is beneficial to identify the weak links of the system and to find out the weak links of the system and The corresponding improvement scheme has important guiding significance for the reliable operation of the current grid and the architecture design of the future energy system. The existing evaluation model is limited to single space security and does not evaluate the power CPS as an organic whole. Based on the above background, this paper mainly deals with the modeling method of electric power CPS, the CPS level of electric power. The risk and its cross space transmission under the system, as well as the security assessment of power CPS are studied. Under the hierarchical structure model, a comprehensive analysis of the security risk of power CPS is carried out from the static power CPS information equipment node risk to the dynamic power CPS chain fault. The specific research contents include the following aspects: (1) research face The power CPS hierarchical architecture model of the object is first analyzed. First, it analyzes the interaction between the power CPS and the energy flow information flow. Then, aiming at the characteristics of the coupling between the power CPS discrete and the continuous system, the object-oriented hierarchical modeling method and structure model are proposed. The model divides the power CPS into the information equipment layer. 5 levels of the sub network layer, network layer, information service layer and physical system layer are used to define the relationship and composition of various levels by object-oriented method. The feasibility of the analysis, evaluation and Simulation of power CPS is improved. (2) the analysis of the risk factors of the power CPS information system under the hierarchical structure is analyzed. The source of the risk of electric power is analyzed. Then, based on the object-oriented hierarchy structure, the fault and risk factors of power CPS are analyzed from 5 levels of information equipment layer, communication subnetwork layer, network layer, information service layer and physical system layer. Finally, the information system fault is classified. The risk of power CPS is deconstructed, and the source of information system fault is clarified. It is beneficial to the analysis and protection of the fault. (3) to study the fault risk assessment method of the power CPS information equipment based on the hierarchical structure model. First, the coupling model of the power CPS information system in the hierarchical structure system is established. Then, an evaluation algorithm based on the hierarchical analysis (AHP) is used as the output function of the coupling model, and the evaluation index is selected as the evaluation index. For the input of the model, the fault risk of the information equipment is the model output. The model considers the static relationship between the information system and the information system and the power system, and can evaluate the static risk of the power CPS information system. Finally, the D2-1 type substation is selected as an example to evaluate the equipment fault risk, and the evaluation results are given. The actual situation is consistent, which validates the effectiveness of the method. (4) to study the cross space transmission mechanism of the security risk of the information system in the power CPS and the security risk assessment based on the improved attack graph. First, on the basis of the analysis of the risk of the information system in the power CPS, the basic mode of the inter space transmission of the electrical force CPS risk is expounded. According to the improved attack map, the power CPS security risk propagation model is set up, which takes information equipment, electric power business and power system fault as node, establishes the risk propagation path, and calculates the sensitivity of the node and attack path to the information equipment fault propagation by improving the attack graph. Force CPS takes comprehensive safety assessment considering dynamic timing.

【学位授予单位】：武汉大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM73

【参考文献】