Study On Key Technologies Of Automation In Intelligent Traction Substation For High-Speed Railway

After the Jing-Guang and Jing-Hu high speed railway line was put into use, China has become a country with the longest operation mileage, the fastest speed and the highest building standard in the field of high speed railway.The specificity of traction load and the complexity of power supply system in high speed railway put forwarda higher requirement for traction power supply technique compared with traditional power supply. The development of intelligent substation techniques affects the power supply system of high speed railway traction deeply. It can be predicted that intelligent traction substation, as an effective measure for improving the efficiency and reliability of power supply, will become a new trend of traction substation.This thesis studied the key techniques on constructing intelligent traction substation. Firstly, the effects of the specificity of the primary systemto the construction of the secondary system were studied by contrastive analysis. And then the construction mode of intelligent traction substation was suggested, based on which the construction of traction substation communication network, the implement methods for the intelligent regional cooperative autonomous technique based on feeding section, and the implantation technique for the open’architecture based generic bayIED were studied and developed intensively.In recent years, the researches on the intelligent substation have attracted wide attention and also make remarkable progress. With the general characteristic of the electric power system, intelligent traction substation can learn the techniques and experiences from the intelligent substation.But high speed railway traction substation is different from electric sustation in several ways such as power requirements, connection modes, electric primary equipment parameters, which will deeply affect the implementation and construction of intelligent traction substation automation system.This thesis presented an intelligent traction substation construction mode with feeding section as a sectionby contrastive analysis. The construction mode constructed a hierarchical control and protect system consist of equipment level, station level and region level with the feeding section as a section. The protective devices were setted near the HV electric equipments. General control cableswere replaced by optical network. In this mode, informations among the devices in one station and among the stations in one feeding section were highly sharing, which facilitated advanced application functions based on feeding section. The proposed mode simplified the system configuration mode of traction substation automation system and improved the security, reliability and economics of high speed railway traction.Highly sharingof information is the primary character of intelligent traction substation. The construction of communication network satisfying the performance requirements is one of the key techniques to be solved during engineering application.The networks performance indicators of communication real-time and delay deterministic, reliability and usability, and security and robustness were theoretical analyzed and the key factors affecting the performance were discussed and improved according to automation application of traction substation. Network construction schemes with the characteristic of traction substation were presented, which devided the traction substation automation devices into system level and device level. The station level networks were used to connect the devices in the system level. And the process level networks were used to connect the system level and the device level.’Data sampling and tripping over network’ mode was used which processed the advantages of high real-time property and high imformation sharing property. According to the characteristics of the network messages of cyclist data, sudden data and routine data and learning from the Internet network trafficmodeling methods, a network traffic mathematical modeling method was proposed for subtraction station, which stated that the sudden data, with Markov property, followed Poisson distribution and routine data, with self-similarity and heavy tailed distribution, could be modeled by Heavy-Tailed’s Pareto distribution.OPNET software was used for dynamic simulation of subtraction station network to test the feasibility of the method. The characteristics of universally applicable networking scheme were analyzed.As an important part of intelligent traction substation, the implementation patterns of intelligent regional cooperative autonomous technique based on feeding section were researched. AT fault location system was used to present a GOOSE based AT fault location method, which fused the data synchrony and network communication together to ensurethe reliability and high real time quality. Private channel and high accuracy GPS were not necessary for this method which reduced the instruments investment and acquired more openness and interoperability. The fault location principle of suck current rate in AT neutral point had the problems of section miscarriage and low fault location accuracy.The causation of fault location accuracy error was analyzed according to the local short circuit test data and practical application to propose a compensation method for fault location accuracy improvement, which had successfully used for AT fault location systems in many high speed railways in China.Considering that the improvement of intelligent traction substation is a long and gradually process, open platform structure based bay level IED implementation method was proposed due to the requirements of bay level IED. The method can support the existing normal data acquisition and control output scheme and also can support the full digital input/output scheme based on information sharing facing the future. The IED instruments using this method had passed the tests of national authority and the IEC61850interoperate test and had been applied in the practical application.At last, the main work of this thesis was summarized and the development trendwas prospected.