基于前推回推的重复接地配网潮流算法

配电网中与中性线和重复接地有关的物理量对于电能质量和系统安全至关重要。目前关于这方面的计算研究不多,而且仅有的方法存在错误和不足。针对这种情况,基于重复接地三相四线制配电网详细模型,提出了一种改进的基于前推回推的重复接地配电网潮流算法。该方法将接地阻抗视为恒阻抗负荷,且对不完全支路和未接中性线的中性点进行特殊处理。改进的方法准确地反映了配网的实际模型,能准确的计算中性线和重复接地有关的物理量。该文以一个重复接地的低压29节点不平衡配电系统作为算例,仿真结果验证了该文算法的有效性、准确性和通用性。

Power flow in multigrounded distribution networks based on the backword-forward technique

In distribution networks,physical quantities on the neutral wire and multigrounding are critical to the power quality and the security of system.At present,there is little research about these physical quantities,and the only methods have some mistakes and shortages.To solve these problems,on the basis of the detailed model of three-phase four-wire multigrounded distribution networks,this paper presents a power flow method for multigrounded distribution networks using backward-forward technique.This method treats grounding impedance as constant admittance load and deals with incomplete branches and neutral nodes without neutral wire specially.The proposed method can reflect actual model of distribution networks and calculate physical quantities on the neutral wire and multigrounding accurately.Results obtained from a case study using low-voltage 29-bus distribution system with unbalanced load and multi-grounded neutral nodals are presented and discussed.Simulation results show its efficiency,accuracy and generality.