葛洲坝电厂125 MW机组的效率状况分析

通过多年来对葛洲坝水电站125MW机组相对效率的现场测试，发现已运行10多年的机组的效率与投产初期差异较大。经分析认为，影响机组效率的主要因素有：由于泥沙磨损造成的间隙增加和叶形变化导致的漏水量增加和效率下降；多种因素造成的协联关系不正确，影响机组的效率及稳定性；排沙底孔的开启对机组效率的影响等。进一步深入开展机组的相对效率试验，探索其变化规律，确定与之对应的协联关系，是电站经济运行和开展设备状态检修的重要措施。

Analysis on the efficient situation of 125 MW generating unit of Gezhouba Power Plant

Based on the field tests on the relative efficiency of the 125MW generating units in Gezhouba Power Plant for these years, it is found that the efficiency of the generating units when they have operated for more then ten years has big differences in comparison with their initial operation stage. The analysis showed that the main factors of affecting the unit's efficiency are as follows. The increasing gaps caused by sediment abrasion and increasing water leakage caused by the blade type change can result in the drop of unit's efficiency. The incorrect coupled relationship caused by many factors can affect the efficiency and stability of generating unit. The opening of bottom holes for discharging sediment also can affect the unit's efficiency. Therefore, further developing deeply the test on the relative efficiency of generating unit, exploring its efficiency change laws, and determining the corresponding coupled relationship are the important measures for realizing the economic operation of power plant and developing the situation check of equipment.