针对交直流混联微电网这类新型网络的潮流分析问题,建立了Droop型分布式电源以及AC/DC逆变器并网稳态潮流模型,并根据并网点电压对称进行三相、单相并网模型的相序分量转换。利用序电流补偿法将AC子网解耦为三序网络且并行求解,显著减小了问题求解规模;进一步建立了AC/DC逆变器两侧交流频率和直流电压耦合关系,有效解决了两子网间功率平衡问题。在序分量体系下提出了适用于直流微电网多种方式接入的孤岛交直流混联微电网三相解耦潮流算法,基于IEEE等标准配电系统的修改算例,验证了所提算法的有效性、适用性以及高计算效率。
For analyzing the power flow of hybrid AC/DC microgrid,the steady-state power-flow models of Droop-type DG(Distributed Generation) and grid-connected AC/DC inverter are established and the phasesequence component conversions based on the voltage symmetry of grid-connecting point are carried out for the three-phase and single-phase grid-connection models. The sequence current compensation method is applied to decouple the AC network into three sequence networks to greatly reduce the solving scale,and the relations of coupling between AC frequency and DC voltage are constructed for both sides of AC/DC inverter to effectively maintain the power balance between two sub-networks. A three-phase decoupled power-flow algorithm suitable for different integration modes of DC network is proposed based on the sequence components of islanded hybrid AC/DC mircogrid. The proposed algorithm is applied to different modified IEEE standard distribution systems,verifying its effectiveness,applicability and efficiency.