Risk Analysis Of Power System Cyber Attack And Digital Watermark Based Cyber Security Defense

With the development of digital、information of power system, there is a new risk sourcegot into people’s horizons—Cyber attack, it has the characteristics of the destructive. With theconcept of smart grid proposed and popularity of ICT, power system has developed to CyberPhysical System. With the development of cyber communication and the application ofnetworked control, cyber attack will have more and more influence on power grids, it willbecome the core of the smart grid.It’s no doubt that cyber age’s approaching provide hotbed for cyber attack, power systemare physical separated at present, but it is still not secure absolutely. As stuxnet can attacklocal area network (LAN), this thesis catch the topic of security of SCADA, and summarizeddefense measures of cyber attack, analyze fragile information system of power grid, thenproposed opinion of initiative defense technology.According to cyber security and IS construction in electric company, the thesis madeclassified description and comparing analysis of cyber attacks which target to power girds.Combined with power law distribution as analysis index, discussed the relationshipbetween cyber attack and blackout. The result of analysis show that cyber attack can leadhuge risk, meanwhile, the result also can put more sight on the viewpoint that power system isfragile while confront to cyber attack.As huge destruction cyber attack can give rise to, the thesis propose a method based ondigital watermarked which can cope to cyber attack, utilize digital watermarked which usuallyused in picture、voice frequency, grafting to real time data transmission in power system, datavalidation function achieved by digital watermarked which hidden in original data. This thesisselects cyclic redundancy check code as digital watermarked, Finally, simulation model isestablished, feasibility and reliability of the method have been validation deeply.