Algorithms for Locating and Characterizing Cable Faults via Stepped-Frequency Waveform Reflectometry

Abstract

The paper presents algorithms to realize effectively and accurately the stepped-frequency waveform reflectometry (SFWR), i.e. the reflectometric technique based on the use of sinusoidal bursts. This technique is useful for monitoring the health status of connection cables, but has many other applications, like other reflectometric techniques. The paper outlines the theory of SFWR, highlighting the problems associated to the transient components in the reflected signals; presents a method to minimize the effect of the transients, estimating the frequency response function (FRF) of interest with very low systematic error; shows how to use the FRF to locate and characterize faults in cables; evaluates accurately, using simulated cables with exactly known characteristics, the errors associated to the proposed methods. Overall, the paper demonstrates how the SFWR technique can be effectively used for testing cables, and in general determine, via reflectometry, parameters of interest of transmission lines.

Detection and Characterization of Multiple Discontinuities in Cables with Time-Domain Reflectometry and Convolutional Neural Networks

“…As demonstrated in [ 21 ], using the SFWR technique, a measure of and can be obtained for any value of . In particular, they can be measured in a range of frequencies of interest and then used to derive an estimate of the primary parameters of the TL in those frequencies.…”

Research on cable fault detection method based on attenuation compensation technology

“…According to equations ( 6), (7), and ( 8), the input impedance and reflection coefficient of the cable are functions of the original parameters, frequency, and position of the cable. The integral transformation method can be used to convert the broadband impedance spectrum or reflection coefficient spectrum from the frequency domain to the spatial domain, thus achieving the positioning and identification of cable faults and local defects.…”

“…In recent years, Frequency Domain Reflection (FDR), also known as Broadband Impedance Spectrum (BIS), has become a research hotspot in cable diagnosis and fault location due to its higher sensitivity. It achieves the location of cable faults or local defects by analyzing the reflection signal characteristics generated by the linear sweep signal injected into the cable head at discontinuous points [6,7]. Reference [8] proposes to use the measured first end reflection coefficient spectrum to achieve fault localization through discrete Fourier transform (DFT).…”

Accurate Detection and Localization of Water Pipe Leaks through Model-Based TDR Inversion

“…TDR-based techniques also drastically reduce the amount of time needed for inspection compared to conventional leak detection techniques; in fact, hundreds-of-meters-long pipes can be inspected with a single measurement operation. Besides, TDR is a well-established technique already used for many applications such as detection and localization of cable defects [ 9 , 10 , 11 , 12 ], monitoring of landslide [ 13 , 14 ], characterization of antennas [ 15 ] and measurement of dielectric properties of materials [ 16 , 17 ], of liquid level in tanks [ 18 ], of soil moisture [ 19 ], of water diffusion in irrigation [ 20 ] among many others, even in the biomedical field [ 21 ]. A possible disadvantage of TDR-based water leak detection is that the SE must be installed near the water pipe, and, hence, it is difficult to use the technique in existing pipelines.…”