水电机组一次调频贡献电量影响因素研究

采用数值仿真的方法开展了水电机组一次调频贡献电量的影响因素分析，建立了水电机组一次调频仿真数学模型，采用实际电网频率变化过程作为调速器频率输入，分别对调速器在开度模式和功率模式下的一次调频过渡过程进行了仿真计算，分析了调速器参数、水轮机非线性特性及水流惯性时间常数对一次调频贡献电量的影响。通过研究可知: 增大调速器 PID 参数或降低调差率可提升一次调频贡献电量，水轮机在最小水头下一次调频贡献电量明显偏低，调速器开度模式下水轮机水头和负荷变化对一次调频贡献电量的影响更大。而且，水流惯性时间常数 Tw 越大一次调频贡献电量越小。研究成果明确了调速器参数、水轮机特性以及水流惯性对水电机组一次调频贡献电量的影响规律，对水电机组的优化运行具有重要的指导意义。

Study on factors of influence on electricity contribution of primary frequency modulation of hydropower unit

The factors of influence on electricity contribution of the primary frequency modulation of hydropower unit are analyzed herein by means of numerical simulation，for which a mathematical model for the simulation of the primary frequency modulation of hydropower unit is established，and then the simulative calculations on the primary frequency modulation transient processes of the governor under both the opening mode and the power mode are respectively carried out through taking an actual power grid frequency variation process as the input of the governor，thus the influences from the parameters of the governor，the non-linear characteristics and the water flow inertia time constant of hydro-turbine on the electricity contribution of the primary frequency modulation are analyzed． It can be known from the study that the electricity contribution of the primary frequency modulation can be raised by increasing the PID parameter or decreasing the adjustment rate of the governor，while the electricity contribution of the primary frequency modulation of the hydro-turbine is obviously lower under the minimum head and the influences from both the head and the load variation of the hydro-turbine are more significant under the opening mode of the governor． Moreover，the larger the water flow inertia time constant is，the less the electricity contribution of the primary frequency modulation is to be． The laws of the influences from the parameters of governor，hydro-turbine characteristics and flow inertia on the electricity contribution of the primary frequency modulation of hydropower unit are clarified by the results of this study，while an important guiding significance for the optimal operation of hydropower unit is provided as well．