Summary
Bentonite is widely used as a filling material in underground ducts for high-voltage cables due to its high thermal conductivity, which enhances heat dissipation and enables optimization of conductor sizing. However, even localized application failures may create hot spots that reduce the system current-carrying capacity and accelerate insulation aging. This paper proposes a noninvasive method to assess bentonite filling quality during the project execution phase. The method is validated through simulated filling failures and is based on circulating high-intensity direct current through the cable metallic screen to induce heating, monitored by an optical fiber– based Distributed Temperature Sensing (DTS) system. Thermal profile analysis allowed accurate detection and localization of anomalies, which were eliminated after corrective actions. The proposed approach enables early detection and correction of installation defects prior to system energization, ensuring adequate thermal performance and preventing future operational failures.
Additional informations
| Publication type | Session Materials |
|---|---|
| Reference | B1_11021_2026 |
| Publication year | |
| Publisher | CIGRE |
| Country | Brazil |
| Study committees | |
| File size | 843 KB |
| Price for non member | 30 € |
| Price for member | 30 € |
Authors
BRAGAGNOLLE Thiago - Prysmian Brazil; CALIANI Kleber - Prysmian Brazil; BODO German - Prysmian Brazil; LEE Woong - Prysmian Brazil
Keywords
Bentonite, Distributed temperature sensing (DTS), High-voltage cable systems, Thermal conductivity, Underground applications
