基于非线性函数寻优的汽轮机启动规划

Start-up Optimization for Turbine Rotor Based on Nonlinear Function

根据电厂汽轮机运行规程,针对某320 MW亚临界凝汽式汽轮机,利用有限元软件ANSYS对汽轮机转子建立有限元模型.根据该机组的冷态启动数据,计算出启动过程的最大应力曲线,验证启动过程中最大应力的产生位置.改变蒸汽温升率和暖机时间,拟定不同的冷态启动方案,分析不同启动工况的应力大小和启动时间,建立了时间相关项和启动过程中应力的相关模型,并将启动规划问题转换为限定条件的函数最优化问题.在保证汽轮机转子应力满足强度要求的同时,求出最小的启动时间,优化启动曲线.

In accordance with the operating procedures,the Finite Element Method（ FEM）model of the rotor is made by taking a 320 MW steam turbine rotor as the research object. The geometry of the rotor is simplified,and the start-up maximum stress curve is calculated based on the cold start data schedule by utilizing ANSYS. The location of the rotor that the maximum stress occurs during the start-up process is verified. Different cold start-up schedules are designed by changing the steam temperature rise rate and warm-up period,and the maximum stresses and the start times with different start-up schedules are compared. The stress model depending on time during the starting-up process is built. Then the start-up plan is converted into an optimization problem with the restrictive conditions. Ensuring the stress of the rotor meeting with the strength,the start-up curve is optimized with the minimum start-up time.