The Research On Protection Setting Calculation And Its Software Package For Large Hydropower Plant

Hydroelectric power construction is developing rapidly in china at present. According to the requirement of electric power development plan and"west-to-east power transmission", the scale of large hydropower plant is continuously increasing. For making relay protection device plays its role, the setting calculation technology need be improved. Taking the background of Three Gorges project, this paper discusses the research on setting calculation for low voltage auxiliary power system in large hydropower plant and the software package used for setting calculation of large generation-transformer group.The modern large hydropower plant must not only ensure reliable power supply for equipments in it but also provide standby power in emergency. Auxiliary power system becomes more and more complex, including its protection configuration and coordination, so the protection setting calculation is given a higher demand. Taking the right bank power station of Three-Gorges for example, this paper researchs setting calculation for low voltage auxiliary power system in large hydropower plant: Based on analysis of connection mode of auxiliary power system, the model of station service system is built by PSASP; Based on short-circuit calculation, system equivalent is finished; by researching the characteristic of release, the paper solves the problem of protection coordination and proposes a feasible scheme for setting calculation, the scheme has achieved a passing evaluation and has be put into operation.The structure and protection configuration of large generation-transformer group are complex, the set contents are different in the products by different factories. It makes setting calculation complex and manual calculation is error prone. It's an urgent need for designing a software package for setting calculation of generation-transformer group. The paper proposes a design scheme of software package; Based on analysis of protection setting calculation characteristic of generation-transformer group, the basic task and function design scheme of software are defined; Based on research of general structure and database, the implementation technology scheme is defined. The software package is composed of Delphi and SQL Server, realizing the function including the graphics modeling, data management, fault analysis, protection setting computation and fixed value management. Setting calculation module of it takes the mode of user-defined principle. The software system can meet the need for different hydropower plants...