Relay Protection Study Of A Distribution With Small Hydropower

With the rapid development of China's national economy, the power in the growing importance of social and economic life significantly. It can be said that there is no electricity the whole community will be paralyzed. Therefore, a series of measures must be taken to ensure the security and reliability of power grid. Substations are the intermediate links between the power plants and the users, play the role of exchange and distribution of electric energy, its security and stability operation, the rapid development of the national economy is significant.Small hydropower is non-carbon clean energy, it do not exist both resource depletion and pollute environment, it is an integral part of our strategy of sustainable development. But The indraft of small hydropower also bring some new technical problems to the grid, since most distribution network are from a single power structure of radiation, and protection relay of traditional distribution network is designed and operated based on radial network structure.With the small hydropower indraft, not only made the power supply of distribution network from a single power into a many-fold, but also change the line parameter near the small hydro and the level of fault and bring new challenges in protection for traditional distribution networks.In this paper, "Equipment Safety" to "Substations Safety" line of thinking, combined with regional substation (110kV) electrical network, and under the "Electrical Design of Electric Power Engineering Handbook (Electrical second part) ", the protection programs of the main transformer, substation transformer, 10kV Power Capacitor and lOkV distribution line are analyzed and discussed.Through theoretical analysis of the small hydro power substation protection and its original response, and then determine the relay protection scheme selection in areas with small hydro substation, and looking into the hardware structure of microprocessor-based protection devices and protection flow chart, Finally, introduced a relay setting example of the main transformer and substation, it provided favorable basis on design of small hydro substation.