Abstract This paper presents an adaptive approach for distance relay third zone setting. The proposed method uses variational mode decomposition (VMD) approach to decompose the local end current signal into different modes. The signal extracted from the third mode is used to calculate the energy index. The apparent impedance and energy index are used to detect symmetrical and asymmetrical faults in the third zone of the distance relay. The proposed logic also helps the distance relay to operate securely during power swing, voltage instability, load encroachment, generator outage, line outage, and single-pole tripping. The effectiveness of the proposed method is tested using the simulated data generated from the IEEE 39-test bus system model and Indian Power network. EMTDC/PSCAD software is used for simulating the models. Results ensure that the presence of noise in the signal, high resistance fault path and higher sampling frequency has a negligible impact on the performance of the proposed method.

中文翻译：

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自适应距离继电器算法，用于检测和区分系统压力条件下的第三区域故障

摘要 本文提出了一种距离继电器第三区设置的自适应方法。所提出的方法使用变分模式分解（VMD）方法将本端电流信号分解为不同的模式。从第三种模式中提取的信号用于计算能量指数。视在阻抗和能量指数用于检测距离继电器第三区的对称和非对称故障。建议的逻辑还有助于距离继电器在功率摆动、电压不稳定、负载侵入、发电机停电、线路停电和单极跳闸期间安全运行。使用从 IEEE 39 测试总线系统模型和印度电力网络生成的模拟数据来测试所提出方法的有效性。EMTDC/PSCAD 软件用于模拟模型。