水轮发电机组闭环开机特性仿真及优化

针对水轮机转轮叶片裂纹现象,从水轮机调速器的开机规律对转轮的影响角度出发,建立计入非线性环节的电液随动系统模型和基于模型综合特性曲线的水轮机模型,分析按一段直线规律变化的闭环开机特性,提出了考虑水轮机工作水头偏差等因素的综合性能指标,并基于该指标对某水电站机组开机过程进行仿真优化。结果表明,按综合指标优化得到的闭环开机过程有优越的动态性能,减少了开机规律对转轮的影响。

Simulation and optimization of closed-loop start-up characteristics for hydraulic turbines

Aiming at the crack phenomenon in a hydraulic turbine runner blade, from the perspective of the influence of the start-up law of the turbine governor on the runner, an electro-hydraulic servo system model considering nonlinear parts and a hydraulic turbine model based on comprehensive characteristic curves were established. The closed-loop start-up characteristics for hydraulic turbines whose rising curve of the expected rotation speed shows a straight line rule were analyzed. Considering the deviation of working head and other factors, a comprehensive index is proposed. The start-up process of a Francis hydraulic turbine in China was simulated. The results show that the closed-loop start-up process based on the comprehensive index can obtain a strong dynamic performance and reduce the impacts of the start-up laws on the runner.