发电机组参与电网一次调频的特性研究

一次调频是确保电力系统频率稳定的主要途径之一,但目前采用DEH(数字式电液)控制系统的发电机组,通过调节系统设置较大的调频死区,切除一次调频的控制作用,大大降低了一次调频在突发性事故中稳定电网频率的作用。为研究发电机组参与电网一次调频的特性,建立了3区域互联系统的数学模型,并通过仿真试验,分析研究了不同的调频死区参数设置条件下,电网稳定所需要的一次调频容量,确定电网负荷扰动大小与机组调频容量之间的关系,对于指导电网中发电机组调节系统的参数设置和调整以及电网一次调频容量的确定具有重要的指导意义。

Research on characteristics of power system primary frequency control operating on power plants

In power system, primary frequency control (PFC) is one of the important methods to maintain frequency stability. But now the dead band is usually placed in a digital electro-hydraulic (DEH) system, which decreases the function of PFC during contingencies. In order to study the characteristics of PFC of generating units operating on power plants, a mathematical model of a three-area power system was presented in this paper. The relation between load disturbances and PFC ability was analyzed. The capacity of the PFC that is necessary to maintain the power system frequency stability at different dead bands and load disturbances of the system was suggested. It is significant to direct the setting of the parameters of governing systems and PFC capacities of the power system.