水电能源科学

针对水电站输电线路结构复杂、故障点隐蔽性强导致定位效率低的问题，提出一种新的双端行波故障定位方法。首先，采用基于红嘴蓝鹊优化(RBMO)的连续变分模态分解(SVMD)对线模电流行波信号进行分解，从而获得一系列固有模态分量(IMF)以及每个IMF的相应中心频率。其次，利用改进Teager能量算子(NTEO)提取峭度值最大IMF能量突变点，确定初始行波到达线路两端时刻。再次，基于两端确定的中心频率计算出对应的行波传播速度并结合到达时刻推导出频率相关波速的双端行波定位公式。最后，基于PSCAD仿真软件，搭建水电站220 kV输电线路仿真模型来验证所提方法的定位性能。仿真结果表明，该方法在各种故障情境下具有较高的定位精度，定位误差控制在200 m以内。

Aiming to address the issue of low location efficiency caused by the complex structure of hydropower station transmission lines and the strong concealment of fault points, this paper proposed a novel double-terminal traveling wave(TW) fault location method. Firstly, the aerial-mode current TW signals were decomposed using successive variational mode decomposition(SVMD) based on red-billed blue magpie optimization(RBMO), obtaining a series of intrinsic mode functions(IMFs) and their corresponding center frequencies. Subsequently, an improved novel Teager energy operator(NTEO) was employed to extract the energy mutation point of the IMF with maximum kurtosis value, thereby determining the initial arrival time of TW at both line terminals. Then, a frequency-dependent wave velocity-based double-terminal TW location formula was derived by calculating the corresponding wave propagation velocities using the identified center frequencies and combining them with the arrival times. Finally, a 220 kV transmission line simulation model for hydropower stations was established in PSCAD to validate the proposed method. Simulation results demonstrate that the method achieves high localization accuracy across various fault scenarios, with location errors controlled within 200 m.