DC distribution system (DCDS) has many preferable advantages to integrate renewable energy sources and native-DC loads than AC distribution system (ACDS), and the benefits of higher power density, greater energy conversion and wider supply radius can be obtained. In this paper, a methodology of sizing the techno-economic of a medium-low voltage DCDS is proposed. Firstly, the system framework and its equipment composition are stated. Then, considering the distribution capacity, supply ability, operation loss and reliability, the technical indicators of the demonstrated DCDS are analyzed and quantified. In regards to the DCDS's distribution-level and consumer-level, the calculation models of the annual costs are presented. Further, different scenarios are imitated to verify the efficacy of the proposed sizing approach, and the techno-economic comparison is implemented in the DCDS and ACDS with similar structure configurations. The calculation results reveal that the DCDS shows a visible economic performance at the consumer-level, and for the scenario of accessing high proportion DC loads, it is more cost-effective than the ACDS. Finally, the correctness of the cost models is proven, and this study can offer a reliable reference for building the medium-low voltage DCDS.

中文翻译：

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中低压直流配电系统的技术经济选型方法


直流配电系统（DCDS）在整合可再生能源和本地直流负载方面比交流配电系统（ACDS）具有许多优越的优势，可以获得更高的功率密度、更大的能量转换和更宽的供电半径。本文提出了一种确定中低压 DCDS 技术经济规模的方法。首先阐述了系统框架及其设备组成。然后，综合考虑配电能力、供电能力、运行损耗和可靠性，对示范DCDS的技术指标进行了分析和量化。针对DCDS的分销层面和消费者层面，提出了年度成本的计算模型。此外，模拟不同的场景来验证所提出的尺寸确定方法的有效性，并在具有相似结构配置的DCDS和ACDS中进行技术经济比较。计算结果表明，DCDS在用户层面表现出明显的经济性能，对于接入高比例直流负荷的场景，其比ACDS更具成本效益。最后证明了成本模型的正确性，本研究可为中低压DCDS的建设提供可靠的参考。