针对冲击式水轮机在初期设计阶段无合适的综合特性曲线用于电站大波动过渡过程计算的问题,根据冲击式水轮机喷嘴构件的布置特点,推导出喷针行程与喷嘴过流量的关系式,并与模型试验进行了对比,验证了公式的正确性。通过比较公式、孔口出流模型及模型综合特性曲线在大波动过渡过程中的计算结果,得出公式能更好地反映喷嘴流量特性,表明该公式可代替孔口出流模型指导初期设计阶段的冲击式电站大波动过渡过程计算。 Aiming at the problem that the impractical comprehensive characteristic curve of impulse turbine is not used in the initial design stage for the calculation of large fluctuating process of power station, the relationship between nozzle stroke and nozzle overcurrent is deduced according to the layout characteristics of impinging turbine nozzle components. The model test is compared to verify the correctness of the formula. By comparing the calculation results of the formula of the orifice, the model of outlet orifice and the model characteristic curve during the process of large fluctuation, it is concluded that the formula can better reflect the nozzle flow characteristics, indicating that the formula can replace the orifice outlet model to guide the initial design stage Calculation of the Large Fluctuation Transition Process of Impact Power Plant.