基于连续潮流模型的直流配电网负荷裕度分析

直流配电网由于能灵活接纳分布式电源和直流负荷,是未来智能配电网的发展趋势。随着直流配电网中负荷需求的不断增加,系统会由于静态电压失稳而崩溃。因此,研究直流配电网的负荷裕度对保障系统安全可靠运行至关重要。该文首先建立直流配电网的潮流模型,并将含双有源桥DC-DC变换器的潮流模型嵌入到直流配电网潮流模型中,提出了基于连续潮流法的直流配电网负荷裕度计算方法。通过两类典型的拓扑结构的直流配电网仿真,结果表明直流配电网在减小网络损耗和提高供电能力方面明显优于交流配电网,而且DC-DC变换器变比增加有助于负荷裕度提升。

Load margin analysis of DC distribution network based on continuous power flow model

The DC power distribution network is a development trend of the future intelligent power distribution network because it can flexibly accept distributed power and DC loads. With the increasing of the load demand in the DC distribution network, the system would collapse due to the static voltage instability. Therefore, it is very important to study the load margin of the DC distribution network to ensure the safe and reliable operation of the system. In this paper, the power flow model of DC distribution network is established firstly, and the power flow model with the dual active bridge DC-DC converter is embedded in the power flow model of DC distribution network, and the load margin calculation method of DC distribution network based on continuation power flow method is proposed. Through the simulation of two typical topologies of DC distribution network, the results show that the DC distribution network optimizes the AC distribution network in terms of reducing the network loss and improving the power supply capacity, and the increase of DC-DC converter ratio helps to improve the load margin.