三要素法在无限大电力系统短路暂态过程分析教学中的应用

On the Application of Three-Factor Method to Transient Process of the Infinitely Great Electric Power System with Short Circuit Fault

经典法是分析一阶线性电路暂态过程的一种常用的数学方法,要求按照电路定理列出微分方程,然后求解微分方程,计算过程比较繁琐;三要素法是对经典法求解一阶线性电路暂态过程的概括和总结,不必列出和求解电路的微分方程,直接计算出待求响应变量的初始值、稳态值和电路的时间常数即可,具有简捷方便的优点。目前供电工程教材中,采用经典法来求解无限大容量电力系统短路暂态过程的瞬时表达式,计算量较大,其中表达的物理含义不够明确。在实际的教学过程中,教学效果不够理想。采用三要素法来求此过程的瞬时表达式,旨在简化分析过程,帮助学生更好地理解该部分内容。

The Classic Method is the common mathematical method to analyze the first-order circuit transient state,which requires differential equations written out by circuit laws,and its calculation process of solving differential equation is a sophisticated work.Three-factor Method sums up the main points of the Classic Method,which only requires circuit time constant,initial and steady values of the target response,and this method provides the quickest and most convenient way to analyze firstorder circuit transient state.In the current textbooks related to power supply engineering,the Classic Method has been widely used to analyze transient process of the infinitely great electric power system with short circuit fault.Because of calculation complexity and ambiguity of physical meaning,students are difficult to understand the related content.So the Three-factor Method is applied to analyze this kind of problem,aiming to help students understand better.