同步发电机三相短路暂态过程的数值计算—空间矢量法

NUMERICAL COMPUTATION OF THREE-PHASE SHORT-CIRCUIT TRANSIENT OF SYNCHRONOUS GENERATOR USING SPACEPHASOR METHOD

在电力系统电磁暂态计算中,应计及同步发电机内部的暂态过程,以提高计算结果的精度。不少学者已对机—网暂态研究作出了很大贡献[1][2][5]。本文首先导出了以常见的参数,如Xd、X′_d、T′_d、等来表示的同步发电机等值电路中各元件参数的讣算公式,然后用微分导纳和理想电流源模拟等值电路中的各个元件,得到一个新的发电机数学模型;采用该模型计算机端三相短路暂态过程。结果与用文献[5]所提出的方法计算所得结果相一致,说明了它的正确性。这一新的数学模型便于在应用空间矢量法进行机一网暂态计算中实现机一网接口。

The electromagnetic transients of synchronous generators should be considered in computation of the transient in power system so as to improve the accuracy of calculation. Some scholars have made great contribution to the study of machine-network transient [1] [2] [5]. In this paper, the formulae of element's parameters, expressed in terms of common parameters such as X_d, X'_d, T'_detc, are derived at first for the equivalent circuit of generator, and then a mathematical model using differentiating admittances and Ideal current sources to simulate the branches in the circuit is presented.The correctness of this model is proved by comparing the computation results versus that of other methods under three-phase short-clrcuit at machine terminals.This new model is sultable for realization of the connection of machine with network in transient studles using spaccphasor method.