Safe Electrical Wiring and Interconnection System (SEWIS)

Project Information

SEWIS

Grant agreement ID: 101007867

DOI

10.3030/101007867

Project closed

EC signature date 16 November 2020

Start date 1 February 2021

End date 31 July 2023

Funded under

• SOCIETAL CHALLENGES - Smart, Green And Integrated Transport

Total cost

€ 1 072 344,00

EU contribution

€ 797 844,00

Coordinated by

SOURIAU
France

Periodic Reporting for period 2 - SEWIS (Safe Electrical Wiring and Interconnection System (SEWIS))

Reporting period: 2022-08-01 to 2023-07-31

Summary of the context and overall objectives of the project

The increasing electrification of aircraft is an irreversible trend that will intensify in the coming years. The latest aircraft generation is already generating and using more electrical power than the prior generation. In the future, more electrification is expected to happen with a complete removal of the hydraulic system and with addition of high voltage propulsion systems. However, electrification of aircraft in severe environmental operating conditions will increase the risk of electrical power faults that can cause catastrophic aircraft damage during flight. The goal of this project was to develop innovative Safe EWIS for high voltage direct current networks, with a particular attention to human protection against electrical shock. The outcome of the project had to contribute to the development of advanced aircraft utilizing HVDC networks and further contribute to reduction of CO2/NOX emissions and increase of EU competitiveness.

The SEWIS project has helped UNIMAN develop expertise in sensor systems and machine learning algorithms for monitoring high voltage cables in aerospace environments. PhD students will use this expertise to prevent partial discharge at cable terminations. The knowledge gained from SEWIS will be used in existing collaborations with Rolls-Royce and the FABB-HVDC project. The data and knowledge gained will be used in peer-reviewed journals and future funding proposals.

The opto-electric hybrid contact developed within SEWIS is undergoing an international patent process. The SEWIS project increased the technology capabilities of Eaton and Souriau in two domains: integrating optical sensors inside connectors and contacts, and high voltage and high power interconnection for electrical aircraft applications. The SEWIS results reinforced the Eaton – Souriau momentum in investing R&D resources for optical sensing business development

An innovative safety feature based on Airbus patent has been demonstrated on Twinax electrical contact within SEWIS project. Eaton – Souriau will apply for a patent of power contact with shorting clip (safety feature), referring and completing the prior art of Airbus primary patent.

The project results have enhanced the expertise of NEXANS and supported the (commercial) offer of high voltage cable solutions. The experience obtained in the 2-layer coextrusion of the insulation of cables will be used to define the technical specification for the purchase of a new dedicated extrusion line. The results of the project will be further exploited in other collaborative projects, namely EPROPTECH, MOTECH and HEROES. SEWIS together with the other mentioned projects will enable the maturation of the cable technology from TRL4 to TRL6. In addition, the results will be used for the development of cable solutions in flight demonstrators for commercial projects. A patent application by NEXANS is currently going through the process of internal review before submission.

There are two key opportunities that are expected to progress rapidly as a result of this work:
• The use of the Twinax cable and connector by Airbus in a future aircraft with discussions actively continuing between the projects partners to evaluate the final steps that would be necessary to qualify the product.
• The significant benefits that have been shown as a result of the embedded fibre-optic within the cable assembly delivering the capability to identify thermal defects – there is commercial interest in this technology from a number of sources.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

Complete list of Failure mode of HVDC EWIS.
A FMEA was carried out to study the impact of failure modes of HVDC EWIS associated with human safety. This FMEA showed clearly that most of the failure can be avoided with a health monitoring system of the temperature of the components coupled with voltage and current sensors (particularly on the cable sheath). The FMEA showed also that some major risks (like serial arc tracking) cannot be quickly detected using the existing products technologies but can be detected with the technologies developed in the SEWIS project.

Development of connectors, cables, monitoring system and failure predicting system.
The specification of connectors and cables for non-propulsive application (540V DC or ±270V DC) and for propulsive application involving high voltage (1000 VDC) has been defined based on AIRBUS requirements and results of the FMEA. Different connector design concepts were studied with safety features, leading to the integration of an automatic feature in the non-propulsive connector that is detected by the system as an electrical defect and lead to a power switch off. the propulsive connector contains a heat sensor. The cables are designed around these concepts with simulation and testing, the 1000VDC cable a fiber optic sensor is integrated in the center of the conductor. Finally, the level of detection has been assessed and a system comprising microcontroller and voltage and current sensors has been defined to detect failure of the sheath of the cable that could have an impact on the system safety.

Test program redaction, prototype manufacturing and test execution.
For each designed features, a test program has been written and agreed upon with the topic manager in order to validate a Technological Readiness Level of 4. Once validated, prototypes for cable, connectors and monitoring system were manufactured. Assembly issues and how they were overcome were reported for future developments.
Test programs were then carried out as agreed upon. Results proved encouraging in terms of performances, although some issues prevented a TRL4 validation (ie: smoke density and Hydrogen Fluoride concentration for cable, shorting spring overheating for non-propulsive connectors and Voltage proof for propulsive connectors)

The consortium partners aimed to disseminate the results achieved within the project to a larger scientific and industrial communities to maximize the potential exploitation of the SEWIS findings. The findings were presented during a conference and Standards Committees. More events and papers are expected to be occasions to further communicate about the findings.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

The SEWIS project and EU founding allowed Eaton-Souriau, Nexans and UNIMAN to make significant technical progress in high voltage and high power electrical interconnection needs for MEA, leading to the development of the innovation in product design and manufacturing processes.
New cables and connectors products, that introduce innovative safety features such as shorting clip in the power-Twinax contact (electrical shock protection) and temperature FBG sensors in the propulsive cables and connectors, have been developed, fabricated and evaluated.
The test performed at UNIMAN have demonstrated the benefit of the safety features, allowing to limit the risk of fire due to high voltage and high power EWIS fault during flight.
One international patent is pending, and the application of 2 others (cable and power-Twinax contact) will be considered in next steps.
This work, on the improvement of the safety of high voltage and high power, is a contribution to reach the European Union objectives in reducing the CO2, NOx and Noise in the coming years.
With this work, Eaton and Nexans will continue to deliver best-in-class products and services, helping maintaining manufacturing and business activities in Europe.

Derating test AC power voltage - Propulsive