中文摘要：

现有的配电网三相潮流计算模型和算法大部分是在基于中性点理想接地假设的Kron简化基础上,由单相潮流计算方法直接扩展得到,分析的精度和适用的范围有一定的局限性。该文摒弃以往基于Kron简化的三相潮流计算框架,提出精细化的三相潮流计算模型和算法。建立一个能够囊括中低压配电网络各种拓扑结构的、计及各元件接地阻抗的统一模型。模型中将支路元件和端点元件统一采用端口的I-F（U）方程进行描述。给出了构成支路元件的线路、变压器更为精确的模型,并通过在相线变换矩阵中引入附加矩阵项的方法解决了D型变压器的Y参数矩阵奇异问题。将端点元件分成负荷和分布式电源二类,负荷采用IEEE推荐的ZIP模型,分布式电源按各相是否独立控制分为三相控制和单相控制。单相控制方式分为PQ、PI两种。三相控制方式采用三相功率总和为恒定量的模型,并进一步细分为PQ、PI、PV共3种。

英文摘要：

The majority of existing three-phase power flow calculation models and algorithms,which has certain limits both in analysis accuracy and application scope,are obtained by direct extension from single-phase power flow calculation method based on Kron-simplification with assumption that network neutral point is ideal grounding.The refinement three-phase power flow calculation model and algorithm,which discards Kron-simplification-based three-phase power flow calculation framework,was given.A unified model,which covers various topological medium-low voltage distribution networks and includes grounding impedance of all components,was built.The branch component and endpoint component were uniformly described using I-F（U） port model.A more elaborate model for line and transformer,which constitutes the branch component,was given,and the Y parameter matrix singular problem of D type transformer was also handled by introducing an additional matrix in phase-line transformation matrix.The endpoint components were divided into load and distributed generator（DG）,the load was described using the ZIP model recommended by IEEE,and DG was further divided into three-phase DG and single-phase DG according to whether each phase is independently controlled ornot.Single-phase DG was further divided into PQ and PI.Three-phase DG,which employs the control mode of the three-phase power sum constant,was further divided into PQ,PI and PV.