Study On The Key Technology Of Qiaokou 110kV Substation Intelligent Transformation

As the basis endpoint of the grid structure, the intelligent transformer substation is the fundamental basis and important premise of the smart grid construction. The location and size of the substation are considered in the process of the intelligent substation construction. Taking Qiaokou 110 kV substation in Chenzhou City as a research subject, the article analyzes the key technology of the substation intelligent transformation. Base on the basic situation of Qiaokou 110 kV substation, such as location, grid structure, load supply, device configuration, and system component, the author proposes intelligent reform ideas by distinguishing the substation horizontally and vertically in line with their own characteristics, applying the key technology of the substation intelligent transformation. The article works as follows:(1) Through analyzing the operation mode, power range, load condition of Qiaokou 110 kV substation, the author forecasts Qiaokou substation will overload running in the next seven years, with causing safety hazards for the northern grid in Guiyang County. For solving overload problems, the author proposes the necessity of the intelligent transformation for Qiaokou 110 kV substation.(2) Based on "an intelligent equipment, secondary equipment networked" intelligent transformation principle, adopt "once device body + Sensor + intelligent components" program and combined with different voltage levels of the automation system configuration and device status, uses the different intelligent transformation method.(3) The author uses the "once device body + Sensor + intelligent components" program, collects digital information and monitors running status real-time, to achieve intelligent transformation for the once device. For the 110 kV exit line spacing and the entrance line spacing on three sides of the main transformer in Qiaokou substation, the author uses electronic transformer technology to collect digital information on the spot. While for 35 kV and 10 kV exit line spacing, the author retains conventional transformers, and allocates combined units and conventional transformers rationally by the digital acquisition technology of the conventional transformer, to achieve digital transmission for information gathering.(4) In view of the IEC61850 standard,the author proposes automation system transformation for Qiaokou 110 kV substation. Combined with different voltage levels of the automation system configuration and device status, the author uses the method of SV and GOOSE networking for 110 kV line, while using the method of peer to peer network configuration for 35 kV / 10 kV line, through networking comparison. Then, the author sets the process level and the process layer network of Qiaokou substation, implements “Three-Layer and Two-network” automation system structure for the intelligent substation, to build an integrated information exchange platform.(5) The author points out the on-line monitoring need for the power supply terminal equipment and the main transformer in Qiaokou substation. In detail, on-line monitoring technology works for water content of SF6 circuit breakers in the 110 kV exit line spacing and the entrance line spacing on three sides of the main transformer, gas composition and density from oil decomposition in main transformers, and full leakage current of the arrester. Through these methods, the operator can maintain the major equipment’s status, and find adverse running status as soon as possible, eliminating hidden faults in advance, and improving the safe operation level of Qiaokou substation.