A Simulation Study On IEC 61850 Substation Automation Communication

With research of IEC 61850 standard and development of relevant substation automation product, IEC 61850 applied cost has been approved all over the world. It is an inevitable trend that IEC 61850 will replace traditional communication protocol to become mainstream of substation internal network protocol. Great change has occurred in both aspects of network framework and data transmission mode in substation automation system. So understanding IEC 61850 substation communication network performance under different network framework and configure will benefit substation automation devices' development and network design. Due to communication model complexity and locale test limitation, simulation becomes a suitable method to research substation communication network. Electric Power and Communication Synchronizing Simulator (EPOCHS) is an effective tool for simulation study on IEC 61850 substation communication network.IEC 61850 standard's basic concept and kernel technology are expounded in this thesis, including object-oriented modeling, Abstract Communication Service Interface (ACSI), Specific Communication Service Mapping (SCSM) and so on. Based on deep research on program framework of EPOCHS platform, IEC 61850 substation communication simulation frameworks is set up on this platform. A scheme of data exchange between simulation modules for physical device is put forward, and information model and communication model for all kinds of IEDs are made up. All kinds of messages' protocol stack mappings are analyzed, and a design scheme for MMS encoding/decoding module is brought forward, which is used for conversion between ASN. 1 abstract syntax and transfer syntax of MMS Protocol Data Units (PDU). To realize IEC 61850 simulation, several extensions are carried out as follows: IEEE 802.1Q protocol is added to simulate virtual LAN (VLAN). multicast, and sample value (SV) message and generic object-oriented substation event (GOOSE) message are realized; Ethernet bottom channel simulation program is modified, and this platform can simulate both switched and shared Ethernet; buffer queue with multi-priority is designed and realized, and messages are transmitted with priority tag.Substation automation system of a specific substation is set up and its IEC 61850 communication is experimented. The effectivity of extended EPOCHS platform for IEC 61850 communication is proofed. Message delay, jitter and packet loss are compared under different conditions. Based on simulation experiment result, advices for substation device development and communication network design are offered.