Researches on the suitability of switched reluctance machines and permanent magnet machines for specific aerospace applications demanding fault tolerance

In, aeronautical as well as in automotive environments more and more hydraulic auxiliary drives are to be replaced by electrical drives. Applications that are of vital importance for keeping up the operability of the whole system (e.g. movement of the rudders of an aircraft or electrical steering in automobiles) need to be actuated by fault tolerant drives. As switched reluctance machines (SRM) generally offer a very simple and robust design, they are very suitable for high reliable and fault tolerant applications. Permanent magnet machines (PM-machines) on the other hand are known to offer a far higher power density and thus, especially in an aircraft environment, offer the possibility to limit the overall weight and size of the system. This paper compares and evaluates the suitability of SRM and PM-machines for a specific aerospace application