Digital Optical Based Aircraft Actuator Controller Utilizing SiC Power Switches 2012-01-2238

This paper presents an investigation into the feasibility of utilizing commercial off the shelf (COTS) components to implement an optically linked embedded electromechanical actuator (EMA) for aircraft flight control.

A joint 1990s USAF, USN, NASA Electrically Powered Actuator Design (EPAD) program sought to replace hydraulically powered aircraft actuators with those powered electrically, either Electrohydrostatic (EHA) or Electromechanical (EMA). A follow-on NASA research effort in 1992 sought to then replace the electrical control links associated with the EHA/EMA with fiber-optic technology [1][2].

Attempts at implementing an optically-linked EMA while successful, experienced technical challenges and exposed fundamental limitations and shortfalls in some of the COTS technologies available at that time. Owing to limited availability of suitable COTS components, development of optically controlled EMAs has necessitated development and application of custom technologies necessary primarily to satisfy the rigors of the EMA environment.

Market forces driving COTS technological advances have likely mitigated and resolved many of the performance and environmental limitations associated with EMA application of early generation COTS technologies. This appears to be especially true with the electronic data and telecommunications markets driving advances in fiber-optic communication technologies. Similarly, market and regulatory requirements for greater electrical power conversion efficiency have led to advanced switching techniques and improvements in high-power switching devices such as Silicon-Carbide transistors. COTS component sophistication and performance has therefore improved significantly during ensuing decades and certainly warrants another look at COTS component suitability for EMA applications.

This investigation reported herein is intended as a low-cost exploration into the functional and environmental suitability of present-generation COTS components.