PUB - Degradation Identification of an EHA Piston Pump by Analysis of Load-Holding States

Like the evolution in automotive steering from using multiple interconnecting hardware components towards a steer-by-wire system, in aviation current research investigates the development of decentralized actuation options in flight
control systems. The conventional flight control system of the majority of current aircrafts consists of a centralized hydraulic control system.

Content

Authors: Duensing, Yannick; Merkel, Amos; Schmitz, Katharina

To achieve the goal of more electric aircrafts current research investigates the frontline capabilities of
electro-hydrostatic actuators (EHA) as substitution for conventional hydraulic flight control systems. Due to durability
limitations, EHAs are to date only utilized as backup. In this paper the design of EHAs and the impact of the challenging working condition on the health status are presented. A longevity test bench, as well as developed test profile to cover real world operation are explained. Lastly, measurements of load-holding modes are analyzed in detail and insight about runins, temperature dependencies and wear-related efficiency es are gained.