Conventional transmission line distance protection approaches are subject to malfunction under reverse fault-induced current transformer (CT) saturation for the typically employed breaker-and-a-half configuration. This paper addresses this issue by proposing a new distance protection approach that combines the blocking and unblocking criteria of distance protection based on the values of incomplete differential current, operation voltage, and current harmonic content. The proposed approach is verified by theoretical analysis, dynamic simulation testing, and field operation to ensure that the obtained distance protection is reliable and refrains from operating unnecessarily under reverse fault-induced CT saturation in the breaker-and-a-half configuration. Meanwhile, the proposed approach is demonstrated can operate reliably when forward faults occur or various reverse faults are converted to forward faults.

中文翻译：

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电流互感器饱和下的输电线路距离保护

对于通常采用的断路器半配置，传统的传输线距离保护方法在故障引起的反向电流互感器（CT）饱和下会出现故障。本文通过提出一种新的距离保护方法来解决这个问题，该方法结合了基于不完全差动电流，工作电压和电流谐波含量的值的距离保护的阻塞和非阻塞标准。通过理论分析，动态仿真测试和现场操作对所提出的方法进行了验证，以确保所获得的距离保护可靠，并且避免了在断路器半开状态下故障引起的反向CT饱和情况下不必要的操作。与此同时，