中文摘要：

针对未来可再生能源发电容量比例不断提升、传统火力发电机组由承担腰荷的角色向具有深度调峰能力的角色转变的发展趋势,研究汽轮-发电机快速频繁调节出力引起的扭转寿命损耗。利用有限元分析软件ANSYS,建立了汽轮-发电机组轴系模型,得到危险轴段的扭转响应;利用雨流计数法将工作循环应力转化为对称循环下的疲劳应力;考虑负荷的频繁波动,结合Manson-coffin应变-寿命公式和连续损伤理论评估轴系扭转寿命损耗。以国产600 WM超临界汽轮-发电机为例进行仿真,研究扭转寿命损耗与负荷波动性、随机性的关系：随着爬坡率和调峰范围的提高,寿命损耗呈指数增长;权衡机组寿命损耗与可再生能源的消纳,根据机组运行特点选择适当的爬坡率和调峰范围是火电机组将来作为深度调峰机组使用的关键;当考虑负荷的频繁波动特性时,扭转寿命损耗符合累积规则,这是由转子扭转振荡衰减较快造成的。

英文摘要：

As the capacity percentage of renewable energy power generation will increase and the role of traditional thermal power units will change from supporting mediate load to deep participating in peak regulation,the torsional life loss of turbine-generator caused by the quick and frequent power output regulation is studied. The finite element analysis software ANSYS is applied for building the models of turbine-generator shaft system to obtain the torsional response of dangerous shaft segment and the rain-flow counting method is used to convert the working cyclic stress into the symmetrical cyclic fatigue stress. With the consideration of the frequent load fluctuation,the Manson-coffin strain-life formula is combined with the continuum damage mechanics to evaluate the torsional life loss of shaft system. With domestic 600 WM supercritical turbine-generator as an example,the relationship between the torsional life loss and the fluctuation/randomness of load is studied by simulation. The life loss grows exponentially with the increase of ramping rate or peak regulation range. For balancing the life loss of turbine-generator and the accommodation of renewable energy,the key of thermal power units deeply participating in the peak regulation is to select suitable ramping rate and peak regulation range according to the operational characteristics of unit. When the frequent load fluctuation is considered,the torsional life loss conforms to the accumulation rules due to the faster attenuation of torsional oscillation.