Electric Aircraft Concept Research Articles

An overview of the more electrical aircraft

This article introduces the more electric aircraft concept and investigate the potential benefits of the technology for manned aircraft. Typical aircraft electrical power systems and loads are described as well as the exciting, future challenges for the aerospace industry. The importance of power electronics as an enabling technology for this step change in aircraft design are considered and examples of typical system designs are discussed.

Challenges for Health Monitoring of Electromechanical Flight Control Actuation Systems

Flight control systems of civil aircraft have undergone huge developments in the last decades. The current more/all electric aircraft concepts lead to the replacement of the hydraulic actuators in the primary flight control systems by electromechanical systems. Integrating electromechanical systems in safety critical applications implies three main challenges: (a) the detection of all fault cases which could lead to a safety critical state, (b) finding measurement parameters capable to detect faults, and (c) the development of algorithms to detect faults under all flight conditions. Putting the scope on the health monitoring of the mechanical components of a direct drive actuator, a new technology based on piezoresistive thin film sensors (TFS) is presented and its potential shown by using defective ball bearings as an example.

Reliable electro-mechanical actuators in aircraft

There is a general trend in the aerospace industry toward increasing the use of electrically-powered equipment. This trend is usually referred to as Power-by-Wire in the More Electric Aircraft (MEA) concept and it leads, among others, to the substitution of hydraulic actuators by electro-mechanical actuators (EMA). Its benefits are a decrease in maintenance effort and weight, and an increase in efficiency. However, jamming case obstacles stop the massive use of EMAs in flight-control actuators. The aim herein is to introduce the safety needs of electro-mechanical actuators in aircraft applications, and Its major goal is to present the suitability and reliability of such actuator systems, including electric motors and power converters.

Worthy test programmes and developments of smart electromechanical actuators

Early aircraft flight control systems were totally manually operated, that is, the forcerequired to move flight control surfaces was generated by the pilot and transmitted bycables and rods. As aerodynamics and airframe technology developed and speeds increased,the forces required to move control surfaces increased, as did the number of surfaces. Inorder to provide the extra power required, hydraulic technology was introduced.To date, the common element in the development of flight control systems hasbeen, mainly, restricted to this type of technology. This is because of its provenreliability and the lack of alternative technologies. However, the technology to buildelectromechanically actuated primary flight control systems is now available.Motors developing the required power at the required frequencies are now possible(with the use of high energy permanent magnetic materials and compact highspeed electronic circuits). It is this particular development which may make theconcept of an ‘all electric aircraft’ realizable in the near future. The purposeof the all electric aircraft concept is the consolidation of all secondary powersystems into electric power. The elimination of hydraulic and pneumatic secondarypower systems will improve maintainability, flight readiness and use of energy.This paper will present the development of multi-lane smart electric actuators and offer aninsight into other subsequent fields of study. The key areas of study may be categorized asfollows.State of the art hydraulic actuators.Electromechanical actuator system test programmes.Development of electromechanical actuators.Modelling of electromechanical actuators.

Effect of high-temperature aging on electrical properties of Hiperco® 27, Hiperco® 50, and Hiperco® 50 HS alloys

Some more electric aircraft concepts require soft magnetic FeCo materials to be stable at temperatures as high as 773 K for long periods of time. At this high operating temperature, aging related processes may occur that result in changes in material properties. The material supplier typically specifies only room-temperature properties, and only limited reports are available on properties at elevated temperatures. The change in properties as a function of time at 773 K will give information on the lifetime of the material to assist designers when selecting materials for high-temperature applications. We have conducted a study on the effects of long-term aging on the magnetic, mechanical, and electrical properties of Hiperco® 27, Hiperco® 50, and Hiperco® 50 HS FeCo soft magnetic alloys. Samples of each material were aged in argon for 100, 1000, 2000, and 5000 h at 773 K. Here, we report the changes in electrical resistivity after aging. Of the three alloys, high-temperature aging has the greatest effect on the resistivity of Hiperco® 50. The electrical resistivities for each sample are compared and conclusions are drawn on the relative thermal stability of each alloy. The changes in electrical resistivities for each alloy are also related to changes in other properties, such as total power loss and coercivity, that were observed during this study on aging.