Security and Reliability Analysis of A Use Case in Smart Grid Substation Automation Systems

Substation automation systems provide high level of automation for both substation and distribution network. Communication in modern substation automation systems is based on Ethernet, TCP/IP and interoperable protocols within standard network infrastructure. Communication security and reliability become important and must be considered to ensure correct operation of substation automation systems. This paper presents an experimental lab setup in which IEC6180 standard is applied for substation communication. Designing substation LAN with Parallel Redundancy Protocol and programming proxy server supporting Transport Layer Security are proposed for reliability and security of the substation data network, respectively. Also, substation remote communication security is evaluated by testing two communication standards (IEC60870-5-104 and OPC UA) and two types of VPN: PPTP and IPsec. Test results are compared and the most secure solution is proposed. Securing remote communication assures reliable operation of the substation in the distribution network.