一种改进前推回代法的配电网潮流计算

Power Flow Calculation of Distribution Network Based on An Improved Forward /Backward Substitution Method

摘要:

随着电网规模日益扩大,对配电网的要求不断提高,配电网潮流计算成为当前研究热点之一。针对传统前推回代法的局限性进行了一些改进。首先,普通算法在进行迭代计算前必须按一定要求对节点进行编号,而改进算法通过形成3个矩阵能够省略该步骤;其次,将变压器负荷换算到高压侧可以使配电网变为简单的单线图,从而缩小系统规模;此外,用节点注入电流替代回代过程中的节点注入功率能省去支路损耗计算的时间;最后,通过PV节点的无功功率修正方程可以有效地处理含有PV节点的配电网,解决了原方法无法处理配电网系统中PV节点的问题。基于IEEE 33节点配电网系统和某含有PV节点的10 kV系统的对比算例表明所提方法的有效性和可行性。

Abstract:

With the increasing scale of power system，the requirements for the distribution network are constantly increasing， and the power flow calculation of distribution network has become a hot research topic． Aiming at the limitations of the traditional forward/ backward substitution method，some improvements are proposed． Firstly，the ordinary method must number the nodes according to the certain requirements before performing the iterative calculation，but the improved one can omit this step by forming three matrices． Secondly，converting the transformer load to the high voltage side can make the distribution network a simple one － line diagram，thereby reducing the system scale． In addition，replacing the node injection power with the node injection current can save the branch loss calculation time ． Finally ，the reactive power correction equation of PV node can effectively process the distribution network with PV nodes，which solves the problem that the original method can not handle the PV nodes in distribution network system． The validity and feasibility of the proposed method are verified by the comparative simulations on IEEE 33 bus distribution network system and a 10 kV system with PV nodes．