| Popis: |
Nowadays, large aeronautical multinationals, aircraft Original Equipment Manufacturers (OEMs) and their suppliers are immersed in the concept called “More Electric Aircraft”, which will enable the aircraft industry to improve significantly in terms of reduction in aircraft weight, fuel consumption, total life cycle costs, maintainability and reliability. This trend is accelerating in recent years and these companies are investing heavily towards this concept of more electric aircraft, in which traditional hydraulic and pneumatic systems are being replaced by electrically-driven systems. “All-electric" aircraft means that all power off-takes from the aircraft are electrical in nature, thus removing the need for on-engine hydraulic power generation and bleed air off-takes. Removal of the engine hydraulic pumps requires fully-operative electrical power actuators. EMA technologies are already being used in aeronautics, but for safety reasons they are limited to Secondary Flight Controls or military aircraft. Their application to Primary Flight Controls will allow reductions in the weight of drives, gas consumption, and polluting emissions. The major step in moving from EHAs to jam-free EMAs is the prevention of potential jamming cases by appropriate technology and monitoring, thus giving the system aircraft availability for dispatch and failure sizing cases. Including more electronics in the actuators, it is also possible to predict how long an actuator will last, introducing the predictive maintenance instead of preventive maintenance today used by airlines. This is the reason why health monitoring plays a mayor roll in the development of EMA’s. It must be taken into account from the design phase on to the development and deployment phase. In the present paper, a test bench for EMA’s is presented, with a proposal of health monitoring. Different signals, concerning internal signals from the control and others such as acoustic emissions, accelerometers and motor current signature analysis, are analyzed and the result is shown. |
