The characterisation, modelling and detection of series arc faults in aircraft electrical power distribution systems featuring solid state power controllers (SSPCs)

Electrical power demand in aircraft has grown significantly over the last century, and this trend continues with the More Electric Aircraft (MEA) and All Electric Aircraft (AEA) concepts. Higher voltages such as 270VDC are required to deliver additional power to loads and to optimise aircraft mass. Increased voltages inflict more stress on the Electrical Wiring Interconnect System (EWIS) and increase the impact of series arc faults caused by wiring defects. Solid State Power Controllers (SSPCs) are used to provide fast protection in high voltage distribution systems. The aim of this work is the characterisation, modelling, simulation and detection of series arc faults in 28VDC and 270VDC electrical power distribution systems featuring SSPCs. The majority of passive detection schemes in the literature were designed based on empirical data rather than well characterised electric arc parameters, and thus nuisance trips are unavoidable. To address this series arc faults in 28VDC and 270VDC solid state power distribution systems were characterised using the SAE5692 "Loose terminal" method [8], and it was found that 270VDC arc faults cause a minimal ~5.6% reduction in loop current and load voltage compared with ~54% in 28VDC systems. SSPC output voltage transients caused by series arcs were found to be limited by the presence of SSPC snubbers. Increasing the system loop inductance was found to improve series arc stability resulting in fewer arc quench events. Increasing the capacitive load reduces arc stability and causes arcs to quench more readily thus simplifying detection. These results were later used to experimentally validate a novel series arc fault SPICE model based on the static Nottingham V-I model [9] and wider solid state electrical system model. The arc current and SSPC output voltage results were also used to create a prototype passive series arc fault detection system, which has been demonstrated to SAE5692 under laboratory conditions [8]. A novel multilayer PCB current sensor was developed and experimentally validated for this prototype. To further reduce nuisance trips an innovative active arc fault perturbation scheme was simulated and experimentally demonstrated using SSPC modulation to stimulate and detect arc quench. Another novel complementary series arc fault prevention / confirmation scheme was simulated and experimentally validated using SSPC leakage currents. To minimise nuisance trips due to manufacturing and installation errors a unique Built-In Test (BIT) scheme was also developed and experimentally validated using the SSPC to create artificial current and voltage stimuli

Proceedings of the 10th International Conference on NDE in Relation to Structural Integrity for Nuclear and Pressurized Components

This conference, the tenth in a series on NDE in relation to structural integrity for nuclear and pressurized components, was held from 1st October to 3 October 2013, in Cannes, France. The scientific programme was co-produced by the European Commission’s Joint Research Centre, Institute for Energy and Transport (EC-JRC/IET). The Conference has been coordinated by the Confédération Française pour les Essais Non Destructifs (COFREND). The first conference, under the sole responsibility of EC-JRC was held in Amsterdam, 20-22 October 1998. The second conference was locally organized by the EPRI NDE Center in New Orleans, 24-26 May 2000, the third one by Tecnatom in Seville, 14-16 November 2001, the fourth one by the British Institute of Non-Destructive Testing in London, 6-8 December 2004, the fifth by EPRI in San Diego, 10-12 May 2006, the sixth by Marovisz in Budapest, 8-10 October 2007, the seventh by the University of Tokyo and JAPEIC in Yokohama, the eight by DGZfP, 29 September to 1st October 2010, the ninth by Epri NDE Center, 22-24 May 2012 in Seattle. The theme of this conference series is to provide the link between the information originated by NDE and the use made of this information in assessing structural integrity. In this context, there is often a need to determine NDE performance against structural integrity requirements through a process of qualification or performance demonstration. There is also a need to develop NDE to address shortcomings revealed by such performance demonstration or otherwise. Finally, the links between NDE and structural integrity require strengthening in many areas so that NDE is focussed on the components at greatest risk and provides the precise information required for assessment of integrity. These were the issues addressed by the papers selected for the conference.JRC.F.5-Nuclear Reactor Safety Assessmen

NASA Tech Briefs, February 1993

Topics include: Communication Technology; Electronic Components and Circuits; Electronic Systems; Physical Sciences; Materials; Computer Programs; Mechanics; Machinery; Fabrication Technology; Mathematics and Information Sciences; Life Sciences