摘要
大型水轮发电机组转轴系统动态固有频率是机组结构优化设计涉及的最重要技术指标之一 ,现场实测机组轴系固有频率具有十分重要的工程实际意义。本文针对两台 2 0 0 MW以上大型机组振动特性现场实测、转轴系统动态固有频率识别 ,以及尝试采用悬挂重锤 (由 15 0 mm× 16 0 0 mm圆钢制成 ,重 2 .2 k N)对运行中的转轴实施冲击激振试验等内容作了全面介绍。
The natural frequency of a running shaft (It means that the shaft is running.) for large scale hydrogenerator unit is one of the most important parameter in the hydrogenerator structure optimizing design. That the natural frequency was measured infield has very great engineering realistic significance. There are two large scale hydrogenerator units in excess of 200 MW having been measured in situ. As a summa, this paper dealt with the field measurement on the unit vibration, the identification on the natural frequency of running shaft, and the shock excitation test which was tried by means of a hung mass being only a 150 mm × 1 600 mm steel cylinder and 2.2 kN weight. In addition, it must be pointed out that some difficult technical problems existed in the field measurement on natural frequency of the running shaft. In the case of a shaft in static state, it was successful that the natural frequency was identified from impulse response excited by means of the hung mass. But in running state it was failed due to that the impulse response was drown out by the running interference signals. Nevertheless, owing to being very large in unsteady state conditions(such as: the decelerating process, the excess speed test, the cutting off loading test, etc.), the water exciting force might excite the running shaft to produce lower order radial natural attenuate vibration. As a successful example, this paper not only presented the measurement situation of a 200 MW unit while decelerating, but also gave out the recorded vibration waves, the frequency spectra and the data result of the natural frequency.
出处
《机械强度》
CAS
CSCD
北大核心
2000年第1期7-11,共5页
Journal of Mechanical Strength
基金
国家自然科学基金会
机械工业部技术发展基金! (5949370 2 )
关键词
水轮发电机
转轴
固有频率
现场测试
参数识别
hydrogenerator, running shaft, natural attenuate vibration, natural frequency, field measurement, parameter identification
