计及变压器与SOP损耗特性的柔性互联配电网优化调控策略

Optimal Regulation and Control Strategy for Flexible Interconnected Distribution Network Considering Loss Characteristics of Transformers and Soft Open Points

基于智能软开关(SOP)的柔性互联技术为解决现有配电网中潮流复杂、轻重载等问题带来了新的机遇。然而,既有SOP优化调控策略仅以线损最低为优化目标,忽略了变压器与SOP等关键设备的损耗变化特性,无法实现系统的最优运行控制。为此,文中提出一种计及变压器与SOP损耗特性的柔性互联配电网优化调控策略。首先,分析SOP与变压器的损耗特性,得到了两者效率特性曲线;然后,建立了改进损耗灵敏度模型以确定SOP最优接入位置,建立了上层以年度综合费用最低、下层以系统综合损耗最低为目标的双层优化模型,确定SOP最优安装容量,并由下层优化模型实现SOP、变压器以及网络线路损耗的综合优化;最后,基于IEEE 22节点与IEEE 15节点互联系统进行验证。结果表明,所提调控策略相比既有策略更具优势,可大幅降低系统综合损耗,解决系统轻重载问题并提升其运行经济性与可靠性。

The flexible interconnection technology based on the soft open point(SOP) brings new opportunities to solve the problems of complex power flows and light and heavy loads in existing distribution networks. However, the existing optimal regulation and control strategy of SOP only takes the lowest line loss as the optimization objective, ignoring the loss variation characteristics of transformers, SOPs and other key equipment, which cannot realize the optimal operation and control of the system. To this end, this paper proposes an optimal regulation and control strategy for flexible interconnected distribution networks considering the loss characteristics of transformers and SOPs. First, the loss characteristics of SOPs and transformers are analyzed to obtain the efficiency characteristic curves of both SOPs and transformers. Secondly, an improved loss sensitivity model is established to determine the optimal access location of SOP. And a two-layer optimization model is established, in which, the lowest annual comprehensive cost and comprehensive system loss are taken as the objectives of the upper and lower layers,respectively. Then, the optimal installation capacity of SOP is determined, and the lower-layer optimization model realizes the comprehensive optimization of the loss of SOPs, transformers and network lines. Finally, the verification is based on the IEEE 22-bus and IEEE 15-bus interconnection system. The results show that the proposed regulation and control strategy is more advantageous than the existing strategies, which can significantly reduce the comprehensive system loss, solve the system light and heavy load problems, and improve the operating economy and reliability of the system.