Research On The Security Of Message And Its Real-time In Smart Substation

The smart substation is an important part of the smart grid. As a typical cyber-physical system, the information security of smart substation is essential to the security and stability of the power network. The openness of power system communication network, the standard substation network, and increasing network attacks for power system all make it urgent for the research on the information security of smart substation. Comparing with general IT network, the substation network has strict requirement of real-time performance, and it is non-interruptible. With the goal of proposing information security solutions which can satisfy security and specical characteristic of smart substation, this paper researches the cyber security, the security of message and the real-time performance of message with security scheme,the secret key management of smart substation.Firstly, following the attack process for the smart substation of the hacker, this paper analyzes the attack path to access the substation network, and proposes corresponding blocking measures. Then,the cyber security demands are determined through analyzing the cyber security attack methods for the smart substation after the attacker has accessed the substation network. At last, the corresponding cyber security protective measures are gived.Secondly, to solve the security issue of the substation message, this paper analyzes the basic theory of modern cryptography including data encryption algorithm, cipher block chaining, message authentication code and so on. Then, the information security threats and information security demands of three key substation message including GOOSE, SV and MMS are analyzed. Combining modern cryptographic algorithm and IEC 62351 standard which makes some suggestions for the security of substation message, a message security scheme based on HAMC is proposed in order to guarantee the data integrity and authenticity of GOOSE and SV. And a message security scheme based on authenticated encryption is proposed in order to guarantee the data integrity, authenticity and confidentiality of MMS. At last, this paper gives the implementation procedure of these three message security scheme.Thirdly, to verify whether the substation message can meet the requirement of real-time performance or not while taking the proposed message security scheme into account. This paper firstly analyzes the component of message time delay and the requirement of real-time performance for substation message in IEC 61850 standard. Then, according to the characteristic of substation message, the data processing time of the proposed message security scheme in ARM and PC is measured. Furthermore, this paper gives the end to end transmission time of smart substation message in different scene through the simulation of one real 220 k V smart substation on OPNET.Finally, to meet the demand of secret key management for smart substation. This paper firstly analyzes existing secret key management scheme. Then, a new key management scheme suited to smart substation is proposed on the basis of one existing typical key management scheme based on symmetric cryptographic algorithm. The proposed key management scheme mainly includes key distribution scheme and key update scheme based on symmetric cryptographic algorithm.