A Three-Phase Microgrid Restoration Model Considering Unbalanced Operation of Distributed Generation
A Three-Phase Microgrid Restoration Model Considering Unbalanced Operation of Distributed Generation
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DOI：
10.1109/tsg.2016.2621412
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发表时间：
2018-07
影响因子：
9.6
通讯作者：
Zeyu Wang;Jianhui Wang;Chen Chen-Chen
中科院分区：
文献类型：
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作者：
Zeyu Wang;Jianhui Wang;Chen Chen-Chen
最近发生的严重停电凸显了美国提高电网弹性的紧迫性，美国提出了微电网形成方案，以在停电发生后恢复关键负载。大多数配电网络都具有不平衡配置，单相模型无法充分详细地表示这些配置。本文提出了一种采用三相网络模型来表示不平衡配电网的微电网组建方案。问题公式具有带有混合整数线性约束的二次目标函数。三相网络模型使我们能够检查分布式发电机（DG）的三相功率输出，防止可能导致DG跳闸的不平衡运行。由于DG不平衡运行约束是非凸的，因此提出了一个迭代过程，在每次优化迭代后检查是否满足DG的不平衡运行限制。我们还针对不平衡操作约束开发了相对保守的线性近似来处理更大的网络。与迭代求解过程相比，保守线性逼近能够以有限程度牺牲最优性为代价加速求解过程。 IEEE 34 节点和 IEEE 123 测试馈线的仿真表明，所提出的方法产生了更实用的微电网形成结果。此外，本文还探讨了DG和储能（ES）装置的协调运行。 ES 的不平衡三相输出与 DG 的相对平衡输出相结合，可以为不平衡负载供电。该案例研究还验证了 DG-ES 的协调。
Recent severe outages highlight the urgency of improving grid resiliency in the U.S. microgrid formation schemes are proposed to restore critical loads after outages occur. Most distribution networks have unbalanced configurations that are not represented in sufficient detail by single-phase models. This paper provides a microgrid formation plan that adopts a three-phase network model to represent unbalanced distribution networks. The problem formulation has a quadratic objective function with mixed-integer linear constraints. The three-phase network model enables us to examine the three-phase power outputs of distributed generators (DGs), preventing unbalanced operation that might trip DGs. Because the DG unbalanced operation constraint is non-convex, an iterative process is presented that checks whether the unbalanced operation limits for DGs are satisfied after each iteration of optimization. We also develop a relatively conservative linear approximation on the unbalanced operation constraint to handle larger networks. Compared with the iterative solution process, the conservative linear approximation is able to accelerate the solution process at the cost of sacrificing optimality to a limited extent. Simulation in the IEEE 34 node and IEEE 123 test feeders indicate that the proposed method yields more practical microgrid formations results. In addition, this paper explores the coordinated operation of DGs and energy storage (ES) installations. The unbalanced three-phase outputs of ESs combined with the relatively balanced outputs of DGs could supply unbalanced loads. The case study also validates the DG-ES coordination.