RME Cables & Energy
The laboratory's work on the behavior and durability of cables for RME applications aims to better understand the behavior of the studied cables, which may contain different materials and have a complex internal structure. It also aims to better define the durability of the studied cables, particularly with regards to fatigue or environmental stresses. Two categories of cables are currently being studied:
- Metallic or synthetic mooring cables
- Energy transmission cables.
Oceagen is a research and development project supported by ADEME under the Investments for the Future program, which pursues two main objectives:
· Validate, under real conditions, the hydrodynamic behavior of the Ideol offshore wind turbine floater
· Qualify new components for the anchoring system Indeed, offshore platforms are held by anchoring systems composed of cables and chains attached to the seabed.
The SMC laboratory contributes to this project as part of the qualification of these permanent anchoring cables. The modularity and workspace offered by the cable fatigue testing bench has allowed for the best possible characterization of the dynamic behavior of offshore platform anchoring cables using an experimental device. The objective was to adapt the actual operating conditions of these cables subjected to fatigue loading on the SMC laboratory's fatigue testing bench. The fatigue tests consisted of stressing the floater anchoring cable of the offshore wind turbine in such a way as to vary its radius of curvature (simulating the stresses mainly due to waves), combining tensile and flexural forces representative of other stresses such as currents and winds. The real-time detection and location system for defects, CASSC, developed in the laboratory was used during the tests. The results obtained in terms of duration curve were compared to existing standards.
The main objective of the SEASNAKE project is to bring about a radical change in the overall performance of a medium voltage cable system while ensuring its reliability and reducing the risks associated with ocean energy production installations:
I) Increase the economic viability of OWC systems by reducing energy costs by at least 20% - with validated solutions/systems in a relevant environment, achieving TRL7
II) Reduce risks and optimize operations at sea
III) Demonstrate dynamic cable solutions
IV) Minimize impact on the environment.
To understand the challenges and optimize components, more sea testing and numerical modeling of loads are needed. Through established methodologies, further certification of solutions is planned within the project. A successful project strengthens the maritime cluster in Europe and creates innovative solutions that can be used in other offshore applications and benefit the export sector. The project team includes the entire value chain, from cable manufacturing to end-users, including coating manufacturers, operation and maintenance, universities, and testing facilities. It connects the ocean energy sector across Europe to the entire value chain from offshore test sites in Portugal, end-users in Ireland and Sweden, and testing facilities in France to Mo specialists in the UK who bring their unique expertise. This project involves 13 European partners for a total budget of 1.3 million euros. SMC/MAST is responsible for WP3 "Cable design, manufacturing, and validation" and receives a grant of 174.5 k€ for a budget of 232.5 k€.
The majority of overhead power lines have been in service for several decades and are subject to several degradation phenomena. ACSR conductors, the most commonly used, are subject to several weathering phenomena impacting their electrical and mechanical properties. One well-known degradation phenomenon on metallic structures is corrosion degradation, the consequences of which are poorly studied on power lines.
The main objective of the thesis was to quantify the influence of the geometric structure of ACSR wires and cables, as well as the effect of lubrication on NaCl-type corrosion. Therefore, the first task was to carry out accelerated corrosion tests, in which several samples of electrical conductors were corroded according to specific and controlled climatic parameters. On the other hand, a microscopic and metallographic analysis of the corroded samples was performed, studying the impact of the corrosion suffered by these samples on their mechanical parameters using tension, torsion and fatigue tests. The results from the mechanical tests were correlated with the metallographic observations in order to link the damage mechanisms occurring on the wires with the mechanical property losses observed on the wires.
This thesis was carried out in collaboration with the University of Sherbrooke.
Well established in Europe, offshore wind power has a global potential that could reach over 100 GW by 2030. Floating wind turbines are estimated to represent 10% of the market, exploiting offshore sites where the available wind potential is up to four times higher than for fixed turbines. Compared to the foundations of a fixed wind turbine, a mooring system is easier to install and adapts more easily to the geological characteristics of the installation site.
Floating offshore wind power, whose mooring system is an essential element, can quickly become a competitive alternative. Current floating wind sites are located in shallow to moderate depth waters, where a standard catenary mooring is not suitable. A semi-rigid mooring composed of synthetic lines ensures more effective restoring forces and dynamic damping. With a reduced ground footprint of up to two times, the polyamide cable is a promising solution.
The Monamoor project aims at developing modeling tools for the mechanical behavior of nylon fiber lines and appropriate long-term monitoring instruments, based on a deep understanding of material degradation mechanisms. The SMC laboratory will be involved in the evaluation of acoustic emission monitoring of these cables.