Candidate: Henri Carlo Belan
Program: UFSC / POSMEC
Date: March, 2018
Advisor: Victor Juliano De Negri
Co-Advisor: Petter Krus
Abstract: Hydraulics is a technology widely used in mobile systems, such as aircraft and vehicles, especially because they feature characteristics of high power density, robustness and fast dynamic response. However, hydraulic systems are also known to have low energy efficiency, especially when compared to electrical systems. Digital hydraulics is a technology that, according to recent research results, is a promising alternative for a reduction of energy dissipation in these systems. In this sense, this work focuses on searching for more efficient hydraulic systems solutions for aircraft, through the application of digital hydraulics concepts. For this purpose, a concept has been selected which involves the replacement of proportional valves or servo valves by a set of on/off valves associated with the use of multichamber actuators and multiple pressure lines. The energy dissipation reduction obtained by this proposal is associated to the absence of resistive control by orifices, decrease of internal leakage and regenerative configuration. This thesis also includes an elaboration of control and sizing techniques. A feedback position control in association with feedforward strategies, has been evaluated, with fixed and adaptive parameters. The result is a new configuration for hydraulic actuation systems for aircraft (Digital Hydraulic Actuator – DHA), with more energy efficiency and able to meet the requirements of position pursuit dynamics and disturbance rejection. The proposal has also shown a potential alternative for implementation of redundancies. The research was conducted both theoretically and experimentally and carried out in partnership with the University of Linköping, Sweden and SAAB AB.
Reference: BELAN, H. C. Sistemas de atuação hidráulicos digitais para aviões com foco em eficiência energética. 2018. 198 p. Tese (Doutorado em Engenharia Mecânica). Universidade Federal de Santa Catarina, Florianópolis.
