基于柔性直流技术的一种交直流混合配电网可行性研究

Feasibility study of AC/DC hybrid distribution network using VSC-based DC technology

随着配电网中负荷的快速增长和分布式电源迅速发展,传统配电网需要进行一定的升级改造才能满足新增负荷和分布式电源的需求。立足于"手拉手"式接线的传统中压配电网结构,提出了利用柔性直流技术构建交直流混合配电网的改造方案,对其网架结构和控制策略进行了介绍分析。之后,以辽宁省某供电区域为例,对建设交直流混合配网、增建交流配电网和增建直流配电网三种配电网改造方案的经济性进行了对比分析。分析证明交直流混合配电网具有最低的系统运行损耗,当配电网运行年数超过5年时,建设交直流混合配电网具有最低的总投资费用。最后,分析总结了交直流混合配电网的综合优势和发展前景,证明了交直流混合配电网能够成为配电网改造的可行方案。

With the rapid growth of load and prompt development of distribution generations （DG） in distribution network, traditional distribution network requires to be upgraded to meet the needs of new added load and DG. Based on the traditional medium voltage distribution network with hand in hand wiring method, the reformation scheme of AC/DC hybrid distribution network is proposed using voltage source converter （VSC）-based DC technology. In addition, the structure and control strategy of AC/DC hybrid distribution network are introduced. Taking a power supply region in Liaoning province as an example, the economics of three kinds of reformation schemes, i.e. constructing AC/DC hybrid distribution network, building up AC distribution network, and building up DC distribution network, are compared and analyzed. Analysis proves that AC/DC hybrid distribution network has the lowest operating loss. When operating years of the distribution network is more than 5 years, constructing AC/DC hybrid distribution network has the lowest total investment cost. In the end, the paper summarizes the comprehensive advantages and development prospect of AC/DC hybrid distribution network and then manifests that the AC/DC hybrid distribution network can be a feasible reformation scheme of the distribution network.