Summary
The methodology for very low frequency (VLF) withstand testing and cable fault location has traditionally involved distinct operational phases, requiring separate equipment and logistical coordination. This paper proposes and validates a synergetic workflow using a VLF test equipment with Arc Pre-Location (APL) integrated. Such a device allows one to bridge the gap between routine maintenance and fault location. In this study the performance of this integrated function has been assessed concerning physical challenges such as signal attenuation, different insulation types, and intermittent faults, ultimately aiming to shorten the turnaround time for grid maintenance.
Read more Read lessThe main method evaluated is the APL function. It operates continuously during VLF testing and utilizes the high-frequency transient waves generated by an insulation breakdown to calculate the distance to the fault and process data using automated algorithms. To improve reliability on a wide range of faults, particularly for fluid-impregnated cables as Paper Insulated
Lead Cover where faults may self-heal, the system employs an automated voltage sequence that triggers multiple arcs to generate a statistical confidence level for the fault location. The authors validated this approach by collecting data from 23 faulty cables, including mixed configurations, recording a total of 263 transients. The results demonstrate that the recorded transients by the APL function were suitable to derive the fault distance with an accuracy comparable to the established decay method. The study confirms that the integrated workflow allows operators to immediately transition from a "failed"
VLF test to fault pre-location without equipment changeover, shortening maintenance shutdowns.
Additional informations
| Publication type | Session Materials |
|---|---|
| Reference | B1_12005_2026 |
| Publication year | |
| Publisher | CIGRE |
| Country | Austria |
| Study committees | |
| File size | 493 KB |
| Price for non member | 30 € |
| Price for member | 30 € |
Authors
KRUIJEN Joseph - b2 electronics GmbH; DAS MERCES JOAO Stanislava - b2 electronics GmbH; GAJDOSOVA Lenka - b2 electronics GmbH
Keywords
Arc Pre-location - APL - Cable Fault Location - Very Low Frequency - Medium Voltage, Long Cables, Synergetic Workflow, Intermittent Faults, Transient Analysis
