To alleviate the impact of output uncertainty of renewable energy sources (RESs) in unbalanced active distribution networks (ADNs), this paper proposed a two-time scale robust optimization method for the multi-terminal soft open point (SOP). In the long-term scale, the operation points of the SOP were optimized by semidefinite programming (SDP) model to minimize system loss and mitigate voltage unbalance. An improved iterative cutting plane (ICP) method was proposed to strengthen the exactness of the SDP rank-one relaxation. In the short-term scale, V ² - P and V ² - Q droop control mode was implemented in the SOP to better respond to the output uncertainty of RESs. Then a slope robust optimization model was established based on long-term operation points and short-term forecast data to improve system robust security. To coordinate these two time scales, a co-optimization re-dispatch strategy was proposed in the short-term model so that the robust safety margin could be further expanded in extreme conditions. Case studies show that the proposed method can fully utilize the flexible power flow regulation ability of the multi-terminal SOP to reduce system loss, mitigate voltage unbalance and guarantee system robust security in the presence of RES output uncertainty.

中文翻译：

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非平衡主动配电网多终端软开放点的二次规模鲁棒优化调度方法

为了减轻可再生能源（RES）在不平衡主动配电网（ADN）中的输出不确定性的影响，本文提出了一种用于多终端软开放点（SOP）的两尺度鲁棒优化方法。从长远来看，SOP的工作点通过半定编程（SDP）模型进行了优化，以最大程度地减少系统损耗并减轻电压不平衡。提出了一种改进的迭代切割平面（ICP）方法，以增强SDP秩一松弛的准确性。在短期内，V ² - P 和 V ² - 问SOP中采用了下垂控制模式，以更好地响应RES的输出不确定性。然后基于长期运行点和短期预报数据建立了边坡鲁棒性优化模型，以提高系统的鲁棒性。为了协调这两个时间尺度，在短期模型中提出了一种共同优化的重新调度策略，以便在极端条件下可以进一步扩大鲁棒的安全裕度。案例研究表明，该方法可以充分利用多端子SOP的灵活潮流调节能力，以减少系统损耗，减轻电压不平衡并在存在RES输出不确定性的情况下保证系统的鲁棒性。