频繁低幅次同步振荡引起的轴系扭应力在线评估  

Real-time Estimation of Torsional Stress in Turbo-Generator Shafts Caused by Frequent Subsynchronous Oscillation with Low Amplitudes

作　　者：顾煜炯[1] 陈东超[1] 徐婧[1] 任治政[1] 何成兵[1] 

机构地区：[1]华北电力大学国家火力发电工程技术研究中心,北京102206

出　　处：《动力工程学报》2015年第1期37-44,共8页Journal of Chinese Society of Power Engineering

基　　金：国家自然科学基金资助项目(51075145);北京市自然科学基金资助项目(3132015);中央高校基本科研业务费专项资金资助项目(12ZX01;JB2014198)

摘　　要：提出了一种新的高压直流输电(HVDC)系统中频繁低幅次同步振荡(SSO)引起的轴系扭应力的在线评估方法:利用实时采集的扭角信号以及发电机三相电压和三相电流信号,结合轴系的扭振振型和轴系危险截面的扭转刚度,实时计算轴系危险截面的扭矩;根据轴系危险截面处的结构特点和理论应力集中系数求得轴系危险截面处的实时扭应力.应用该方法分析了某1 000 MW机组在发生频繁低幅SSO后的轴系危险截面扭应力的变化情况.结果表明:所提出的扭应力在线计算方法避免了复杂的数学计算,易于计算机实现,且计算结果准确、可靠.A novel method was proposed to realtimely estimate torsional stress in turbo-generator shafts caused by frequent subsynchronous oscillation （SSO） with low amplitudes in high-voltage direct-current （HVDC） power transmission systems, with which the torque in each weak cross section of shafts can be calculated by combining the torsional angle signal and 3-phase generator voltage and current signals collect- ed in real time with torsional vibration modes and torsional rigidity in each weak position, and subsequent- ly real-time torsional stress can be obtained based on the weak section structure characteristics and stress concentration factor. The method was used to estimate the torsional stress history of shafts in a 1 000 MW turbo-generator set, which had suffered an actual SSO with low amplitudes caused by HVDC. Results show that the proposed real-time calculation method for torsional stress is simple, accurate and reliable without complicated mathematical calculation, which is easy to implement via computer.

关 键 词：汽轮发电机组 高压直流输电 次同步振荡 扭振 扭应力 

分 类 号：TK263[动力工程及工程热物理—动力机械及工程]