Concept of experimental EHAS power pack design

EHAS (Electro Hydrostatic Actuation System) is progressive technology used in the design of advanced aircraft hydraulic systems. This paper describes the design process of an experimental EHAS power pack, which is suitable for already built fourth generation inherently unstable combat aircraft. The power pack is going to be modified to fit in available commercial parts uncertified for aviation, for instance power relays, ultra capacitor cells, control blocks, sensors, etc. Still, relevant results for an optimal power ratio between the power source, EAU[7] (Electronic Accumulator Unit), and the hydraulic accumulator determination are expected. Due to better energy distribution control, it will be possible to set the power pack to several operation modes, such as economic, normal, high performance and emergency modes. It is intended to perform series of measurements to make clear if several power pack operation modes are as beneficial as expected. Verification of the EAU capabilities is another part of the intended experiment. Moreover, it is planned to measure ultra capacitor heat generation and to observe behaviour of the power pack during simulated EAU malfunctions.