交直流混联配电网谐振交互作用分析

Resonance Interaction Analysis for Hybrid AC-DC Distribution Network

设备类型多样、拓扑结构复杂是交直流混联配电网的重要特征,传统方法通过对交直流侧子网等效建模进行谐振特性分析,不利于表征两侧子网间的交互作用。为此,提出了一种无须对子网进行等效的交直流混联配电网交互作用模型构建方法,可适用于两侧均为多节点分布的复杂电网,并通过分块矩阵体现交、直流侧节点电压与注入电流间的对应关系。基于该模型研究了两侧子网间的谐振交互作用机理,分析了谐振频率的交互规律和谐振幅值在两侧子网间、子网内部的谐振放大风险频域。最后,搭建了交直流混联配电网仿真模型,对所提方法和分析结论进行了验证,并从节点的谐振参与程度以及元件参数的敏感性方面给出了交互谐振抑制思路。

Multiple equipment types and complex topology are important characteristics of hybrid AC-DC distribution networks.Traditional methods analyze the resonance characteristics by the equivalent modeling of AC-DC-side subnets,which is not conducive to characterizing the interaction between the subnets on both sides.Therefore,this paper proposes a method to build the interaction model of the hybrid AC-DC distribution network without the need of the equivalent of the subnets,which can be applied to complex power grids with multiple nodes on both sides,and reflect the corresponding relationship between node voltages and injected currents on both AC and DC sides through a block matrix.Based on this model,the mechanism of resonance interaction between subnets on both sides is studied,and the interaction rule of resonance frequency and the resonance amplification risk frequency domain between subnets on both sides and within the subnets are analyzed.Finally,a simulation model of hybrid AC-DC distribution network is built to verify the proposed method and analysis conclusions,and the resonance suppression idea is given from the resonance participation degree of nodes and the sensitivity of component parameters.