Adaptive fault detection method, which is compensating the wave attenuation along the propagation, is proposed in this article. Long cable system installed in the factory need to develop precise fault detection method considering propagation dispersion. Using the derived time delay between the incident and reflected wave which is generated from the fault, fault can be localized. The time-frequency cross correlation (TFCC) is a signal scanning process based on the similarity of the energy spectrum for detecting the reflected signal mixed with the noise. The threshold value in TFCC is a reference constant value for judging whether or not a fault is present. Due to the attenuation and dispersion of signal along the propagation, a new threshold value function considering attenuation and dispersion is needed. We propose the adaptive threshold curve for compensating the signal attenuation. We design the equivalent circuit of target cable ( $\text{7}\,\text{m}$ length) and optimal reference signal based on the comparative analysis between the results of computer simulation and actual experiments of $\text{7}\,\text{m}$ length cable. Based on the designed equivalent circuit of target cable( $\text{7}\,\text{m}$ length), a long cable system is modeled by simulation and the performance of the proposed method is proved through the simulation under the various noise level environments.

中文翻译：

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基于时频域反射法的自适应阈值曲线高级信号检测方法

本文提出了一种自适应故障检测方法，该方法可以补偿沿传播方向的波衰减。考虑到传播扩散，工厂安装的长电缆系统需要开发精确的故障检测方法。利用从故障产生的入射波与反射波之间的导出时间延迟，可以定位故障。时频互相关（TFCC）是一种基于能谱相似度的信号扫描过程，用于检测与噪声混合的反射信号。TFCC中的阈值是用于判断是否存在故障的参考常数值。由于信号沿传播方向的衰减和色散，需要考虑衰减和色散的新阈值函数。我们提出了自适应阈值曲线来补偿信号衰减。我们设计目标电缆的等效电路（ $ \ text {7} \，\ text {m} $ 长度和最佳参考信号）基于计算机模拟结果与实际实验之间的比较分析 $ \ text {7} \，\ text {m} $长电缆。根据目标电缆的等效电路设计 $ \ text {7} \，\ text {m} $ 长度），通过仿真对长电缆系统进行建模，并通过在各种噪声水平环境下的仿真证明了该方法的性能。