电力系统潮流计算毕业设计论文.doc

摘要 电力系统的潮流计算在电力系统稳态分析和电力系统设计中有很重要的作用，潮流计算也是电力系统暂态分析的基础。潮流计算是根据给定的系统运行条件来计算系统各个部分的运行状况，主要包括电压和功率的计算。到目前为止，利用电子计算机进行电力系统的潮流计算的算法已经出现了很多，其中应用最为广泛的是基于牛顿——拉夫逊法的潮流计算方法。 在利用计算机进行电力系统的潮流计算之前，需要对网络的节点进行划分和编号，建立电力网络的数学模型，即电力系统的网络方程式。本文主要介绍了节点导纳矩阵的形成方法。在形成节点导纳矩阵之前，需要将电力网络进行等值电路的变换，其中主要包括输电线路和变压器的等值电路的变换。 由于牛顿——拉夫逊潮流计算对于初值的给定有比较高的要求。因此在进行牛顿——拉夫逊迭代计算前，先采用高斯——赛德尔迭代法产生一组比较精确的初值。本文详细介绍了高斯——赛德尔法和牛顿——拉夫逊法迭代计算的过程。其中主要内容有迭代方程式的建立，雅克比矩阵的计算，功率和电压的计算，以及在迭代过程中PV节点转化为PQ节点时的处理方法。开发工具采用Matlab编程语言，采用读写Excel电子表格的方法进行数据的输入和输出。 本文采用一个5节点的网络进行实例分析，用Matlab开发的计算程序进行潮流计算，计算结果表明程序的算法具有良好的收敛性和实用性。 关键字：潮流计算，节点导纳矩阵，牛顿——拉夫逊，高斯——赛德尔，Matlab Abstract Power flow calculation has a very important role in power system steady-state analysis and power system design, and it is also the basis of transient analysis in power system. Flow calculation is based on given conditions of the power system and calculates the operational status of every part of the system, including voltage and power. So far, there are kinds of algorithm which use the electronic computer in power flow calculation, the most widely used algorithm is the Newton - Raphson power flow calculation method. Before we the computer in power flow calculation, we need to need to have the nodes of the network classified and numbered and establish a mathematical model of power network, namely the power system network equations. This paper describes the formation of the node admittance matrix . In the formation of the node admittance matrix, we need to transform the power network to equivalent circuit, which includes transformation of transmission lines and transformers. The Newton - Raphson power flow calculation has a relatively high demand for a given initial value. So before the Newton - Raphson iteration, we use Gauss - Seidel iterative method to produce a more precise initial value. This paper describes the process of Gauss - Seidel and Newton - Raphson iteration. The main contents are the establishment of iterative equation, the calculation of Jacobian