中文摘要：

考虑到目前直流负荷逐步增加的现状,以及交直流混合微电网的发展趋势,文中建立了以降低单位发电成本、换流损耗,提高自平衡率为目标的并网型交直流混合微电网多目标优化配置模型。并针对该模型,提出了相应的交直流混合微电网运行控制策略。采用实际工程数据,通过改进非劣排序遗传算法（NSGA-Ⅱ）进行了求解。得到了不同直流负荷比例下的交直流混合微电网优化配置结果,以及直流负荷比例增加对优化配置的影响,并将结果与传统交流微电网进行了对比,验证了所提出的优化配置模型和方法的合理性和有效性。

英文摘要：

Considering the increase of DC loads and the development of hybrid AC-DC microgrid, a muhi--objective optimal sizing model for the grid-connected hybrid AC-DC microgrid is developed for reducing the unit generation cost and converter losses and improving the self-balancing capabilities. Then a control strategy of hybrid AC-DC microgrid for the model is proposed. Based on the data from a practical project, the model is solved by improved non-dominated sorting genetic algorithm （NSGA- Ⅱ ）. The optimal sizing results of the hybrid AC-DC microgrid under different DC load ratios are obtained, as well as the influence of the increasing DC load ratio on optimal sizing. The comparision of optimal sizing results between the conventional AC microgrid and the hybrid AC-DC microgrid has verified the effectiveness and feasibility of the approach proposed.