Study On Auxiliary Power System Opertion Mode Of Three Gorges Hydropower Plant

The Three Gorges hydropower plant is not allowed to blackout in a large area, because of its importance, regardless of power generation, flood control and navigation.In view of this, in addition to the enough consideration of power station’s main system, the service power supply’s safety and reliability are indispensable guarantee.As the paint’s construction, the service power supply is also constantly improved. How to overcome the unresolved weakness of service power supply’s design,make it provide power constantly,ensure safe operation of units and project,it is the important subject before us.This paper mainly analysis the risks of Three Gorges Hydropower Plant’s service power supply,the reliability of various typical operation and how to select appropriate operation mode to avoid risks.Firstly,this paper introduces the structure of Three Gorges Hydropower Plant’s service power supply(mainly includes left bank ,right bank of power plant’s ,power station and dam area networking system) and its main features such as multi-power supply,cross-wiring and so on.Secondly,the paper analysis the risks of this stage and the long-term stage ,such as deadly effect of unit stop results of tripping of Ge Chen line which is the power station’s only output channel,and unit stop due to faults of auxiliary equipments.From these actual situations,the paper selects four possible operation modes,uses these modes and the reliability theory,it establishs serious models,calculates these models and gets reliable data.Thirdly,considering the effects of switching operation and Ge Chen line,it makes use of the results to work out units’load lost rate of the left and right bank station’s service power supply.After the analyse and comparision of service power supply’s blackout rate ,this paper selects two operation modes of relatively lower blackout rate, makes them as references,and also analysis theoretical data.While,it draw out that the right bank of power paint’s service power supply is the highest reliable,at present,the left bank of power plant’s service power supply is the second,the power station is the last,in the long-term,the power station’s reliability is more improved and power station is the complement of the left bank of power station’s service power supply.Finally, this paper discusses how to apply these four typical modes.