Candidate: Marcos Paulo Nostrani
Program: UFSC / POSMEC
Date: October, 2015
Advisor: Victor Juliano De Negri
Abstract: In recent years there has been a considerable development in hydraulic systems technology. The technological improvement has been a function of the integration of electronic devices and improvement of the manufacturing processes. However, the hydraulic systems are still normally controlled by the opening and closing the fluid passages making them extremely dissipative and, therefore, with low efficiency. With the increasing awareness to obtain systems which have optimized energy consumption, the digital hydraulics emerges as a more efficient alternative to conventional hydraulic systems. Aiming to achieve new designs of hydraulic positioning systems, this master’s thesis studies the application of a digital hydraulic system in position control applied in a test bench for wind turbines. From the steady state model presented in this master’s thesis, the optimization of the inertance tube and valve switching frequency was possible. The data obtained were used in the transient model of the pitch angle control system in order to check the behavioral characteristics of the system. To validate the dynamic model, experiments were carried out in the Pitch Angle Control Bench that is located in the Laboratory of Pneumatic and Hydraulic Systems of the Federal University of Santa Catarina. The results of this study address the key elements for the correct selection of the inertance tube dimensions and valve switching frequency and also the main advantages and disadvantages of using a digital hydraulic system compared to a conventional hydraulic system.
Key-words: Digital hydraulics, switching hydraulics, pitch angle control, hydraulic positioning systems, hydraulic system design.
Reference: Nostrani, M, P. Estudo teórico-experimental de um posicionador utilizando hidráulica digital de chaveamento rápido: Estudo de caso em bancada de ensaios para turbinas eólicas. 2015. 169 p. Dissertação (Mestrado em Engenharia Mecânica). Universidade Federal de Santa Catarina, Florianópolis.
