基于容量边界与电压边界的潮流模型选择方法

Selection Method of Power Flow Models Based on Capacity Boundary and Voltage Boundary

在对配电网安全域(DSSR)、供电能力以及安全分析进行建模时,针对直流潮流模型选择缺乏量化依据问题,提出了基于容量边界与电压边界的潮流模型选择方法。首先,在DSSR交流潮流模型基础上,提出了容量边界和电压边界的概念。其次,基于馈线长度变化时二者的位置关系寻找临界长度,即容量约束或电压约束主导的分界点。若馈线长度小于主导分界点确定的临界长度,则容量约束更严格,可采用直流潮流模型;反之,电压约束更严格,应采用交流潮流模型。最后,针对中国城市、城镇和乡村配电网,计算得到不同导线型号、功率因数和调压措施的临界长度参考值。同时给出了导则中5类供电区域的潮流模型选择建议。

When modeling the distribution system security region(DSSR), total supply capability and security analysis of distribution network, and in order to solve the problem that it lacks the quantitative basis for the selection of DC power flow models, a method for power flow model selection based on capacity boundary and voltage boundary is proposed. Firstly, the concepts of capacity boundary and voltage boundary are proposed on the basis of DSSR of AC power flow model. Secondly, based on the relationship between the two constraints when the length of the feeder varies, the critical length is found, that is, the dividing point dominated by the capacity constraint or the voltage constraint. If the length of feeder is less than the critical length,the capacity constraint is stricter, and the DC power flow model can be adopted. On the contrary, the voltage constraint is stricter,and the AC power flow model should be adopted. Finally, for the urban, town and rural distribution networks in China, the reference values of the critical length for different wire types, power factors and voltage regulation measures are calculated. At the same time, some suggestions are given to select the power flow models of the five types of power supply areas stipulated in the planning guidelines.