Research On Computer Communication Networks And Systems In Substation

Substation automation technology has been widely used in MV/LV substation systems in China since 90't. Now it has been developed to HV/UHV substation system. With the gradual improvement of the substation automation technology, it brings forward some new demands. There are two very important things. One is that the new and high- powered communication networks are used to meet the demand of technology progress, the other is to set down the international standard of communication protocol of substation automation system, which must be abided by all manufacturer to realize the interoperation among different vendor. This dissertation deals with the two problems mentioned above. It aims to design an appropriate communication networks for the HV/UHV substation automation system, solving the key technical problems the substation automation technology faces when it develops from the MV/LV to the HV/UHV substation system. The significant achievements are as follows: 1. Exhaustive research is performed on the interface of the SIEMENS 8890 RTU Protocol and the CSC2000 substation automation system. A simple and efficient scheme is provided, and furthermore it is the first successful scheme in China. Up to now there have been 3 sets of the systems operating smoothly in substation. 2. In the dissertation, the research on the embedded Ethernet and TCP/IP protocol is carried out thoroughly. The software and hardware of the embedded Ethernet are carefully analyzed. Based on the research of TCP/IP protocol, the bugs of the embedded TCP/IP software are corrected. The multicast function is accomplished successfully. 3. The network scheme with two-level structure for the HV/UHV substation automation system is provided. The scheme not only can meet the requirement of the HV/UHV substation system but also has the maximal compatibility with the existing CSC2000 substation automation system. The gateway of the scheme is designed and has been adopted in 220kV and 500kV substation automation projects. 4. The connection of the embedded Ethernet with the LonWorks and CAN fieldbus is successfully completed and the corresponding gateway is devised. Not only the limitation of the LonWorks fieldbus is discovered, but also different proposal are offered according to different conditions. 5. The scheme of the bay controller based on the embedded Ethernet and CAN is brought forward and the distributed interlock function based on the embedded Ethernet is realized. 6. The future of the embedded Ethernet used in distributed RTUs~ in fault recorders and in SCADAs is analyzed. The approach of connecting with the CEDnet is also provided in the dissertation. 7. The research and analysis of the international standards about substation automation have been done in the dissertation. The properties and scopes of 1EC60870-5 series, 1EC60870-6 series, UCA2.0 architecture and IEC61 850 system are presented.