Abstract This paper offers a novel passive islanding detection scheme for synchronous distributed generations (SDGs) based on the combination of (dδ/dt) and (dPm/dt). By the occurrence of islanding and grid-connected events, the load angle (δ) and mechanical power (Pm) of SDGs will change. These signals will oscillate during non-islanding events, while they will reach a stable point without any oscillation during islanding events. However, during some grid-connected disturbances such as high impedance faults and small capacitor switching, the oscillations of δ and Pm may not be significant. Therefore, the swing feature cannot be a reliable index and can lead to an inappropriate operation. Hence, to select the best parameters, a combination of four parameters, including dPm/dt, dδ/dt, dPm/dδ, and dδ/dPm is employed. The sensitivity analysis to discriminate islanding from non-islanding events has been reported in the presence of SDGs with various inertia constants, voltage levels, and loads. Based on the results, the combination of dδ/dt and dPm/dt has high accuracy and speed in clustering the occurred events. The efficiency of the proposed approach is tested on the IEEE 33-bus system. It is proved that the proposed approach decreases the non-detection zone to 0.01 MW and 0.01 MVAr of the powers nonconformity.

中文翻译：

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一种基于负载角和机械功率参数的同步型DG被动孤岛检测新方案

摘要 本文提出了一种基于(dδ/dt)和(dPm/dt)组合的同步分布式发电(SDGs)无源孤岛检测方案。随着孤岛和并网事件的发生，SDGs的负载角（δ）和机械功率（Pm）都会发生变化。这些信号在非孤岛事件期间会发生振荡，而在孤岛事件期间它们将到达稳定点而没有任何振荡。然而，在一些并网干扰（例如高阻抗故障和小电容器切换）期间，δ 和 Pm 的振荡可能并不显着。因此，摆动特征不能成为可靠​​的指标，并且可能导致不适当的操作。因此，为了选择最佳参数，采用四个参数的组合，包括 dPm/dt、dδ/dt、dPm/dδ 和 dδ/dPm。在存在具有各种惯性常数、电压水平和负载的 SDG 的情况下，已经报告了区分孤岛和非孤岛事件的敏感性分析。基于结果，dδ/dt 和 dPm/dt 的组合在聚类发生的事件方面具有较高的准确性和速度。在 IEEE 33 总线系统上测试了所提出方法的效率。事实证明，所提出的方法将非检测区降低到 0.01 MW 和 0.01 MVAr 的功率不合格。