直流配网线路供电能力分析

随着用电负荷密度逐步增大及大量分布式电源的接入，目前配电网面临着供电能力不足的问题。直流配电网供电容量、线路损耗、各类电源与负荷接入适应性等方面与交流配电网络均有差别。通过对交流供电线路供电能力的分析，推导出直流供电线路在不同约束条件下的供电能力的计算模型，并在假设的不同电压等级及典型负荷分布形式下，分别对常用导线进行了负荷矩与供电距离的比较。由分析可知在计算供电线路供电能力时电压约束和线路损耗约束在交、直流系统中所起作用不同，提出交、直流配电网络线路供电能力计算选取依据，为今后的研究提供参考。

Power Supply Capability of Line in DC Distribution Network

With the gradually increase of electricity load density and the accessing of a large number of distributed generation, the current distribution network is faced with the problem of insufficient power supply capability. The DC distribution network is different from the AC distribution network in many aspects, such as power supply capacity, line losses, the adaptability for all kinds of power and load accessing, etc. Through the analysis on the power supply capability of AC line, this paper derived the power supply capability calculation model of DC line under different constraints, and compared the load moment and supply distance of commonly used wires under the assumed different voltage levels and typical load distribution patterns. It is concluded that, when calculating the power supply capability, the voltage constraints and line losses constraints play a different role in AC and DC systems. Finally, the selection basis was proposed for the calculation of the power supply capability of power line in AC and DC distribution network, which could provide a reference for the far-reaching research in future.