中文摘要：

在电力系统分析过程中，通常采用近似的方式来计及发电机饱和的影响，一般通过额定电压和1．2倍的额定电压处的饱和系数这两个参数以一定的近似形式来计及饱和的影响。为了研究发电机饱和对低频振荡的影响，基于PSSE软件的发电机模型和参数的具体定义，通过对两区域四机系统进行小扰动稳定分析，并考虑不同的发电机饱和形式以及同一饱和形式下不同饱和系数情况下系统低频振荡的频率和阻尼的变化情况。研究表明，忽略发电机饱和的影响和计及发电机饱和的影响将会得到不同的结论，另外，在使用PSSE过程中，考虑发电机饱和时使用不同的饱和形式得到的结论也不尽相同，同时，即使使用同一饱和形式，不同的饱和系数参数对低频振荡的频率和阻尼都有一定程度的影响。

英文摘要：

In power system analysis, the approximate way is used to take into account the impact of generators saturation, generally adopts these two saturation coefficient of the rated voltage and rated voltage of 1.2 times. In order to study the impact of generators saturation in low-frequency oscillations, this paper analyzes the change of oscillation frequency and oscillation damping of low frequency oscillation in the case of considering different forms of generating saturation, as well as different saturated saturation coefficient while the same generating saturation forms through small signal stability analysis of the two regions and four machine system which is based on the model and parameters defined by PSSE. Studies have shown that there will be a different eonelu~i0n between considering and ignoring the effects of generators saturation. In the use of PSSE process, the conclusions may differ from each other when using a different generator saturated form. Even if using the same form saturation, the different parameters of saturation coefficient will affect the frequency and damping of the low-frequency oscillations to a certain extent.