A Study On Information Security Mechanism Of Smart Substation

As the important part of the electrical power system, substation is responsiblefor several important tasks, including the voltage converters, power distribution,control and management of power transmission and distribution. Substation’s safeand reliable operation guarantees the power grid’s security and stability. Smartsubstation, which uses Ethernet as its communication infrastructure, will face withthe security threats same as the common network, especially for the IEC61850andIEC62351standard, which brings the harsh requirements to the real-time and safetyof information transmission. Therefore, it has become a serious issue about how toguarantee the substation’s information safety under the new standards andrequirements.MMS, a commonly used message in digital substation, has been widely appliedin substations’ information transmission. Focusing on the security demands,IEC62351standard puts forwards three safety requirements. Choosing a properalgorithm to meet various security demands will decrease the burden of computationand network equipment. Having the advantages, such as high speed and easy softwareimplementation, AES-CCM algorithm has two safe modes: integrity check andcalibration encryption, which can satisfy the security requirements of MMS messagetransmission. Through analyzing the format in MMS message transmission innetwork layer TPKT and defining the reserved on the basis of the original format, thispaper distinguishes three types of encryption mode and designs an extended securecommunication message model and security transmission algorithm, as well aspresents the time cost analysis of security message transfer algorithm.Focusing on the communication entity authenticatication and network layerpacket encryption key exchanges problem, this paper puts forwards identitypasswords-based encrypted signature algorithm, which is safe, effective and low loadin computation and network, to satisfy substations’ communication systems. Byanalyzing the requirements IEC62351standard to MMS message authenticationrequirements, this paper designs the cryptographic algorithm message, process ofsignature certification, and analyzes the algorithm performance.Finally, this paper studies the influence of safety message to substation networkperformance through the establishment of OPNET-based substation simulationmodels. Through D2-1star network application scenario simulation andcomputational simulation, the result shows the safety message technology performswell in real-time and security.