300MW汽轮机低压缸末级长叶片与轴系扭振的耦合振动  

The Coupling of the Long Blades at the Final Stage of the Low pressure Turbine with the Shaft Torsional Vibrations

作　　者：鲍文[1] 王西田[1] 于达仁[1] 周鸿儒[2] 申秀兰[2] 

机构地区：[1]哈尔滨工业大学 [2]哈尔滨汽轮机厂有限责任公司

出　　处：《汽轮机技术》2000年第2期65-68,95,共5页Turbine Technology

摘　　要：计算分析了３００ＭＷ汽轮机低压缸末级长叶片Ａ_０振型弯曲振动与轴系扭振耦合对叶片安全性的影响。末级长叶片与轴系扭振耦合将使该叶片振动的实际频率避开率低于计算值，当发生严重的两相短路故障时在叶片根部的最大动弯矩远远高出其额定值；如果电网频率偏离５０Ｈｚ，会对叶片安全性产生更为不利的影响。The coupling of the flexural vibration of the long blades at the final stage of the low Pressure turbine with the shaft torsional vibrations, principally occurs in response to the negative sequence excitation effects derived from either an electrical system unbalance or unsymmetrical disturbance conditions. The effect of the coupling vibration on the blade security is evaluated based on a 300MW turbogenerator. The practical frequency avoidance ratio of the blades is lower than the calculated value and the transient flexural torque at the blade roots by far higher than the rated in the case of the severe line to line fault. The worse case occurs when the electric -network frequency departures from the rated 50 Hz.

关 键 词：汽轮机 叶片 轴系扭振 耦合振动 低压缸 

分 类 号：TK263.3[动力工程及工程热物理—动力机械及工程] TN263.6[电子电信—物理电子学]