大型水轮发电机组弹性轴系由电磁参数激发的弯扭耦合振动的研究

STUDY ON BENDING-TORSION VIBRATION OF THE LARGE HYDRO-GENERATOR FLEXIBLE SHAFT SYSTEM EXCITED BY ELECTROMAGNETIC PARAMETERS

利用弹性体非线性振动的能量法研究水轮发电机组弹性轴系在电磁参数激发下弯扭耦合振动规律。揭示了弯曲振动能够激发扭振，两者相互耦合。利用奇异性理论在物理参数空间对共振的分叉形式进行分析，找到抑制共振发生的参数区域，为机组工程设计和安全运行提供理论依据。在弯扭耦合情况下，通过数值分析所得弯曲振动响应的理论结果与实测结果相符。

The energy method in nonlinear vibration of elastic body is utilized to analyse the phenomena of bending-torsional vibration of the large hydrogenerator flexible shaft system excited by electromagnetic parameters. The study shows that bending vibration can excite torsional oscillation appearing. and that the two kinds of vibrations couple together complicatedly. The singularity theory is employed to investigate the bifurcation modes of resonance in physical parameter space to find the range of parameters for controlling resonance, which is of help for the hydrogenerator design and security operation. Under bending-torsion vibration case, the theoretically numerical results of bending vibration responses are approximate to the experimental ones.