Innovative aircraft power management system
Innovative aircraft power management system
Keywords: Aircraft, Electric power systems, Safety
An innovative space- and weight-saving aircraft power management system has been developed by Io Ltd – the modified- COTS supplier – in collaboration with Teledyne Microelectronic Technologies, Ultra Electronics Datel and Paramount Panels. The high-integrity system eliminates the large panel of electro- mechanical circuit breakers that is typically located in the cockpit– plus the associated long runs of cabling – by means of a network of solid-state power controllers interfaced to a simple user panel. The system reportedly provides much more flexible control of the power system, and incorporates a number of safety measures including a failsafe mode that activates in the event of a network or component failure.
“This system improves operational effectiveness and makes a significant contribution to space and weight saving on aircraft, particularly in the all-important cockpit area”, says Io Ltd's Project Manager, Roger Kemp.“It makes an active contribution to the common need to install more electronic systems and equipment on aircraft during refurbishments, and is equally useful for new designs”.
In the new power management system, the circuit breaking or isolation function is performed by small solid- state power control devices instead of electro-mechanical switches. These are housed in small, rugged enclosures that can be distributed around the aircraft, and mounted with the equipment they have to control, or in areas where space is available. The power control units or PCUs are linked via avionics-grade Ethernet to a small keypad/display control panel that may be mounted in the cockpit or other position. Each remote PCU can be populated with up to 96 circuit breakers.
The prototype shown at Farnborough simulates a power management system for the C-130 K Hercules, to demonstrate capability. Individual power circuits may be switched on and off from the user panel, the status of circuits can be monitored, and any circuit trip results in a warning message. In addition to providing basic electrical power control functions, the system may be configured to provide advanced features for faster and more efficient action in emergencies or operational use. These include controlling inter- related circuits as a group, interactive or automatic load shedding, activity logging, and user-accessible “on-line” manuals.
Inherent safety is a key parameter of the design. A major safety feature is a fallback mode that ensures that each equipment's power connection reverts to either on or off – as desired – in the event of a network or component failure. In a typical system, Io Ltd also expects there to be a minimum of two control panels for network redundancy, and any panel can take full control of power management in the event of a failure.
The network backbone is 100 Mbit/ TX Ethernet, while the application is handled by Io Ltd's own communications protocol simple network input/output protocol (SNIP) – which has previously been specified for a major UK military aircraft program. To aid qualification to DO- 178 B (level C and above)for this new application, Io has defined a profiled TCP/IP stack called SNIPStack.
Each group member has provided expertise to this project, giving the system an excellent pedigree. Teledyne has designed a new board-level implementation of its rugged solid- state power controllers. Ultra Electronics Datel is providing user interface, networking, and control software to the top qualification levels required by aircraft standards. Paramount Panels is contributing a display unit design, based on years of experience with air, land and sea projects. All this technology has been integrated into the system by Io Ltd, who are also providing the packaging and acting as prime contractor.
For further information, Contact: Io Ltd, Woodhouse Barn, Swaffham Prior,Cambridge CB5 0HT, UK. Tel: +44 (0) 1638 742390; Fax: +44 (0) 1638 743821; E-mail: roger.kemp@ioltd.co.uk;Web site: www.ioltd.co.uk
