Research Of Substation Data Communication Subsystem Based On IEC61850 Standard

Currently, the presence of the whole power system of digital and information technology level is not high, information sharing and use of resources can not adequately issues. Promulgation of the IEC 61850 standard and Ethernet technologies mature for the development of intelligent substation to provide technical support. IEC 61850 standards common characteristic substation communication networks and devices, and provides for the use of Ethernet as the basic communication technology to build Ethernet-based substation automation system. Different from the traditional Ethernet, Ethernet communication within the substation to delay demanding the presence of real-time data transmission problem in the power system heavy load. Aiming at this problem, combined with the actual situation of the substation, network-oriented research to enhance implementation of real-time Ethernet substation communication networks based on concrete. The main contents include:(1)From its own characteristics IEC 61850 standard system and digital substation, substation packet type classification, a mathematical model to analyze the reasons for the data transmission delay generated, which made way to improve network performance. Comparative advantages and disadvantages of different substation networking, select the three networks substation unified communications network.(2)Based on the analysis VLAN(Virtual LAN) and priority marking the two technologies in the realization of the switch mechanism, proposed the use of these two protocols mechanisms in intelligent electronic devices IED(Intelligent Electronic Device) in the program. The program enables intelligent electronic devices capable of sending packets in accordance with the flexibility to set different data for real-time requirements of the frame priority level, reducing the switch to forward packets during packing and unpacking time, transformed the only switch implementations with an intelligent All messages within a fixed set of electronic equipment a priority, and enhance the ability of digital substation intelligent electronic devices integrated transmission of data, reducing the important packets end to end delay. OPNET network simulation software use than substation SV(sampled value message), GOOSE(tripping packets) in the presence of two types of message exchange mechanism IEDs network transmission delay, simulation results show the proposed scheme to reduce these two packets in Ethernet transmission delay.(3)There is no division in the analysis of the VLAN(Virtual LAN) infrastructure within the substation when the network load on the proposed substation at intervals divided VLAN, this restriction only sampled value message function in this interval to send samples of current and voltage, reducing the network core load switch, reducing overall link utilization. Also proposed inter-VLAN classification time interval according to the substation equipment linkage protection to meet the requirements, and enhance the ability of the process layer GOOSE messages during normal transport and network transmission of real-time traffic suddenly increases both cases. By no VLAN networking solutions and existing contrast, this networking solution to enhance the real-time protection trip GOOSE message communication, reducing the current and voltage sampled value message(SV) occupation of network resources, when a failure occurs, reducing within the busbar protection equipment spacing interval intelligent feeder protection and control commands issued by the transmission delay circuit breaker, to better meet the requirements of the standard. Use OPNET simulation results show that the designed VLAN scheme reduces the network load power during normal operation, and enhance the critical information GOOSE trip in real-time network packet transmission, ensure grid efficient, reliable and safe operation.