考虑负荷电压静特性的有源配电网潮流计算

Power Flow Calculation of Active Distribution Network with the Consideration of Static Load Voltage Characteristics

本文针对前推回代法在计算考虑负荷电压静特性的有源弱环配电网潮流时效率较差的问题,提出了一种新的基于回路分析的前推回代方法。以功率注入节点等效支路、合环支路分别作为连支,形成两种类型回路。负荷电压静特性采用ZIP模型,对恒阻抗负荷形成单独回路,并建立回路电流-节点电压方程。除恒阻抗负荷单独处理外,其他负荷均与PQ、PI、PV型分布式电源进行统一处理,计算节点注入电流,用于前推回代潮流计算。最后,以IEEE33节点系统为算例验证表明,所提出的对恒阻抗负荷形成单独回路,并且直接建立含环网支路的网络方程,可以提高基于回路方程的前推回代法的计算效率。

In light of the lower efficiency of back/forward sweep method when it is used to calculate the active weak-loop distribution network with the consideration of static load voltage characteristics,a new back/forward sweep method is proposed based on loop.Two types of loop are formed by treating the equivalent branch containing power injection nodes and the closed-loop branch as links,respectively.Afterwards,loop current-nodal voltage equations are set up using the ZIP model of static load voltage characteristics,which forms a single loop for constant impedance load.Except for the separate constant impedance load,the other loads and distributed generations(PQ,PI and PV types)are processed together,and the corresponding node injection currents are calculated before they are used in the back/forward sweep calculation of power flow.Finally,an IEEE 33-node system is used as a numerical example,and the result shows that a single loop can be formed for the constant impedance load,and the calculation efficiency of back/forward sweep method based on loop equations can be improved by directly establishing network equations with a closed-loop branch.