三峡水电站水轮发电机组的选择研究

Study and selection of turbine generator units for the Threc Gorges project

三峡水电站26台68万千瓦混流式机组的选择研究,是根据电站主要特性参数及对机组的选择要求,对比分析国内外大型混流式机组的制造水平和典型水电站运行状况,并结合国际专家咨询和国内专家论证初选决定的。在选择水轮发电机组的研究工作中,曾就正常蓄水位175米对比了不同单机容量的选择方案,并认为初步选定的机组容量合理、参数先进、现实可行。针对制造三峡水轮机的关键技术问题:如模型试验及新材料、新结构的应用;计算机辅助设计和制造;加工工艺的进一步完善等,作了较详尽的论述。同时探讨了三峡水轮发电机的关键技术,如改善冷却方式、合理选用电气参数、提高线圈的绝缘水平、改进振动和刚度设计、加强大推力轴承的研制、优化总体结构。在今后实施过程中,将视资金来源、采购方式以及制造厂的设备条件、工程总进度等,对设计方案进一步进行优选。

The Three Gorge Project with normal poor level of 175m contains 26 Francis tur-bine generator units with units capacity of 680 MW. Study and setection of the units are basedon the following considerations: natural condition and project parameters; manufacturing analysisand operation experience available around the world for large units; examination suggestion givenby domestic specialists: and proposals from consultants and manufacturers abroad. Many alterna-tives of units with different unit capacity are being compared. As a result, the 680 M W unit isconsidered as favorable scheme for TGP with reasonable unit capacity, advanced parameters andfeasible manufacturing. In this paper, main key technical problems, such as model test, CAD,application of new materials and structures, CAM, renewal in technology, and technology forcooling system. electrical parameters comparison, insulation of armature and coils, vibration andrigidity, large thrust-bearing, general structure, are discussed. According to the financing re-sources, equipment purchasing mode, construction schedule requirement, the study and designworks for the units will be optimized and then be finalized.