A Novel Diagnosis and Location Method of Short-Circuit Grounding High-Impedance Fault for a Mesh Topology Constant Current Remote Power Supply System in Cabled Underwater Information Networks

Abstract

Cabled underwater information networks (CUINs) have evolved over the last decade to provide abundant power and broad bandwidth communication to enable marine science. To ensure reliable operation of CUINs, it is essential to have the technology for high-impedance fault diagnosis and isolation with high reliability and accuracy. The short-circuit grounding high-impedance fault status of mesh topology constant current remote supply system was diagnosed by analyzing the variation difference of equivalent current in the Laplace transform domain. Shore power feeding equipment (SPFE) supplied the power for underwater system individually from both terminals, and the fault location was located by calculating the shunt loss of the current in the trunk before and after the fault. Thus, the fault was isolated to maintain normal operation of the rest of the system and improve the reliability of CUINs. According to the established typical mesh topology constant current remote supply system circuit model, the fault location scheme was designed to simulate the faults of the cable sections in the different links in the constant current remote supply system, and the changes of current located at the primary nodes (PNs) in the Laplace transform domain before and after the fault were analyzed. The results show that the equivalent current of each PN changes when a fault occurs in the system, and the location of the fault point can be analyzed by comparing the shunt loss of the current in the trunk before and after the fault. The designed method of short-circuit grounding high-impedance fault diagnosis and location for a constant current remote supply system is suitable for the fault monitoring and judgment of CUINs with high feasibility and practicality. Furthermore, it provides technical support for the resulting effective determination of faults, isolation of faults, protection of equipment, and improvement of the system reliability.INDEX TERMS Cabled underwater information networks (CUINs), constant current, short-circuit grounding high-impedance fault, fault diagnosis, point location, reliability.

Analysis of influencing factors on buffer layer discharge for high‐voltage XLPE cable

“…According to the resistance calculation formula of coaxial hollow cylinder, the resistance of the conductor screen layer, the insulation outer screen layer, and the buffer layer can be solved by (4) [25]. where R x represents the axial resistance, R y represents the radial resistance, ρ is the resistivity, r od is the outer radius of coaxial hollow cylinder, r id is the inner radius of coaxial hollow cylinder, L is the minimum unit length in the voltage distribution calculation model.…”

A Transfer Learning-Based High Impedance Fault Detection Method Under a Cloud-Edge Collaboration Framework

“…However, different contact surfaces can affect the arcing phenomenon of HIFs. Therefore, existing methods have mainly been proposed for detecting one specific type of HIF, such as vegetation HIFs [2], [3], soil-grounding HIFs [4], underwater cable HIFs [5], etc. However, an accurate model representing all types of HIFs is almost impossible.…”

Design and Analysis of an Equivalent Load Power-Stability Control Circuit for Cabled Underwater Information Networks

“…Observation and electrical equipment in the networks relies on a remote power supply system connected to shore-based power supply equipment to provide energy. The remote power supply system serves as the energy supply, and its performance determines whether the CUINs can operate normally [11]. At present, the mainstream international submarine cabled power supply technology uses direct current power supply, and there are two types, i.e., the constant voltage system and the constant current system, each system having its own advantages and disadvantages.…”

“…For constant voltage power supply systems, the power converter module is connected in parallel with the trunk cable, and the power can be easily distributed through a mesh network [12], as with the North East Pacific Time-Integrated Undersea Networked Experiments (NEPTUNE-Canada) [13,14] and other operating systems [15,16]. For constant current power supply systems, a high-frequency switching converter is needed to shunt the primary node current on the trunk cable, keep the current in the trunk cable constant, and provide a constant current for the secondary node [11,17], as with Japan 's Dense Ocean Network for Earthquakes and Tsunamis (DONET) [18,19]. A system with a constant current power supply mode is resistant to cable impedance and faults.…”

“…In the event of a short-circuit fault, parts of the system can still continue operating, and the system does not require high-medium-low voltage conversion [20]. Furthermore, the constant current power supply mode has the advantages of modularization and standardization of the electric energy conversion modules [11]. Therefore, the constant current method is a better choice than constant voltage in scenarios where reliability is more important than other features such as efficiency or power delivery capacity [21].…”