国内首例保留原磁轭直支臂更换为斜支臂转子支架改造

Rotor Support Renovation by Replacing the Straight Arms with Oblique Arms while Keeping the Original Yoke:the First Case in China

针对水布垭电厂3号发电机转子支架强度偏弱,局部应力超允许值,将转子支架直支臂改为斜支臂。经计算,新转子整体和局部强度值均在允许范围内,相比较于原结构的直支臂,斜支臂方案的翘曲系数更大,满足翘曲稳定性要求.。通过各工况的稳定性试验、过速试验、甩负荷试验及72 h试运行,机组的各项参数指标均在标准范围内,消除了潜在风险,实现长期稳定运行。

The strength of the rotor support of the No.3 generator in Shuibuya Hydropower Plant is not enough and the stresses at some locations exceed the allowable value.Thus,technical renovation is carried out to replace the straight arms of the rotor support with oblique arms.Calculation shows that the overall and local strength values of the renovated rotor are within the allowable range.Compared with the original straight arm,the buckling coefficient of the oblique arm is larger and satisfies the buckling stability requirement.The results of the stability test,overspeed test and load rejection test under various working conditions,and the 72 hour trial operation show that all parameter indexes of the unit are within the specification range.The potential risk of the unit is successfully eliminated and a long-term stable operation is achieved.