Pilot current differential protection for transmission lines is an important part of ensuring the safety of the power grid. The loss of data synchronization due to cyberattacks and the uncertain compensation degree of controllable shunt reactors will evidently deteriorate the performance of pilot current differential protection and may lead to the maloperation of the protection if no effective countermeasure is implemented. To address the above-mentioned problems, a novel line pilot protection criterion based on the recognition of the phase space trajectory is proposed. First, the basic principle of phase space and its parameter selection scheme are analyzed. Then, the fault component instantaneous power difference (FCIPD) is selected as the time series for phase space reconstruction, and the distribution characteristics of the phase space trajectory of the FCIPD under different conditions are analyzed. Subsequently, a novel pilot main protection criterion for a transmission line is proposed. PSCAD/EMTDC-based simulation results verify that the proposed criterion is immune to timing attack and controllable shunt reactors and has the advantages of free setting, high speed, and high-fault-resistance tolerance capability.

中文翻译：

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抗定时攻击和可控并联电抗器输电线路的基于相空间的先导主保护

输电线路先导电流差动保护是保障电网安全的重要组成部分。网络攻击造成的数据同步丢失和可控并联电抗器补偿程度的不确定性，将明显降低先导电流差动保护的性能，如不采取有效对策，可能导致保护误动作。针对上述问题，提出了一种基于相空间轨迹识别的线路导频保护准则。首先，分析了相空间的基本原理及其参数选择方案。然后，选择故障分量瞬时功率差（FCIPD）作为相空间重构的时间序列，分析了不同条件下FCIPD相空间轨迹的分布特征。随后，提出了一种新的输电线路导频主保护准则。基于PSCAD/EMTDC的仿真结果验证了所提出的准则不受时序攻击和可控并联电抗器的影响，具有自由设置、高速和高容错能力等优点。