The More Electric Aircraft (MEA) concept promises lower fuel consumption, lower emissions, and reduced operating costs. Fundamental to MEA is the replacement of the inefficient and maintenance intensive hydraulic, pneumatic and bleed air powered systems present on today’s aircraft with electrically powered systems. New aircraft designs are beginning to implement 230 volt variable frequency AC and 270-540 volt DC electrical power systems to enable the MEA concepts. The risk of high energy faults and electrical hazards in these higher voltage systems is increased, thus the ability to detect and isolate electrical faults is critical to the MEA. Eaton’s world leading experience in arcing fault detection, including over 100 arc fault patents, can solve these problems.
Eaton proposes to develop arc fault detection modules for 270/540VDC and 230VAC aircraft systems. This will involve the characterization of arcing faults through computer modelling and empirical testing and data acquisition of fault voltage and current signatures. Arc fault test procedures and apparatus will be designed to replicate in a laboratory environment, arcing faults representative of what would occur in an actual aircraft. Normal operational voltage and current signature profiles of existing electrical loads will also be acquired to facilitate nuisance trip immunity in the detection algorithm design. Using computer-based analysis and modelling, arc detection algorithms will be developed. The Eaton team will also explore system design options to limit arc occurrences and damage. Performance of the detection algorithms will be verified against the fault and load signature database. Arc fault detection modules will be designed and built to implement the algorithms. These prototype modules will be integrated into power distribution switching components. Finally, the Eaton team will provide technical support for field testing and verification of the integrated AFD/switching device solution.
Eaton is the world leader in arc fault protection technologies. The Cleansky Arcing and Next Generation Airplane Power Hazard Abatement project provided an opportunity to investigate and develop techniques applicable to the new high power aircraft circuits. This project enabled extensive testing to characterise arcs from both Alternating Current (230VAC) and Direct Current (270-540VDC) sources. An opportunity was also taken to ‘cross reference’ computer modelling techniques with actual testing. Arc recognition algorithms were developed and integrated into two demonstrator units. Testing was also conducted to establish the ability of the algorithms to accept electrical loads working under normal conditions as benign. The demonstrator units were supplied to the Cleansky Joint Undertaking following internal validation and initial integration with a new Power Distribution System.
This project allowed Eaton to extend the existing R&D for aerospace experience in the development of numerous Arc Fault Detection Circuit Breaker (AFCB) designs for 120VAC 400Hz (single and 3- phase) and 28VDC aircraft power distribution. Therefore foreground techniques were developed in the collection of arc characteristics at the higher voltage levels (270-540VDC and 230VAC). Foreground algorithms were developed to recognise the arcs and new demonstrator arc detection modules were produced.