计及阻抗匹配平衡牵引变压器的电网短路计算方法

摘要

By analyzing in-depth the connection mode of theimpedance-matching balancetraction transformer, two practical methods respectively based onsymmetrical component and phase component are proposed to calculate the short-circuit current of power grid when short occurs in the secondary side of the transformer. And the formulas for a variety of fault types are given. Thecomparison oftwo methodsis also proposed. An example using actual grid is given to prove the accuracyandpracticability of the two methods. The method based onsymmetrical component can be adopted in nowadays calculation programs widely applying in power system based onsymmetricalcomponent more conveniently than the method based on phase component and the calculation programs can calculate the short current rapidly by adding special module usingsymmetrical component when short occurs in the secondary side of the transformer. A software package based onsymmetrical component has beenapplied in the actual project.%深入分析了阻抗匹配平衡牵引变压器的接线形式，分别提出了基于对称分量法的计及阻抗匹配平衡牵引变压器的电网短路计算方法以及基于相分量法的短路计算方法。给出了各种类型的故障计算公式。并将两种方法相比较，结合算例验证了方法的正确性和实用性。与基于相分量法的短路计算方法相比，基于对称分量法的短路计算方法更容易与现有普遍应用的基于对称分量法的电力系统故障计算程序相结合，只需在程序中添加相应的短路计算模块即可对阻抗匹配平衡变压器短路故障进行计算。利用所提基于对称分量法的计算方法开发的软件包已用于实际工程。