A master thesis from Aalborg University
Implementation and Control of Low-Power Auxiliary Functions in Electro-Hydraulic Variable-Speed Drive Networks
Term
4. term
Education
Publication year
2025
Submitted on
2025-05-27
Pages
91 pages
Abstract
This project investigates the incorporation of low-power auxiliary functions into an electro-hydraulic variable-speed drive network, used for a two-link crane following a pre-determined trajectory. The auxiliary function requires a supply pressure of 300 bar. The system is modeled using existing control methods, and tracking performance and the calculated maximum torque experienced by the drive shafts of the motors provide a base-line. To examine the effect of connecting auxiliary functions directly to the network, three structures are adapted so that the grabber is supplied by each one of the control volumes. Two separate control methods that maintain a constant control volume pressure are developed. Both control methods accurately track the trajectory and maintain the required supply pressure in the relevant control volume, without being sensitive to disturbances from the grabber. Connecting the grabber to control volume three provides the best tracking performance and lowest motor shaft torques. When the grabber is supplied by control volumes 1 and 2, high pressures result in large torques applied to the motor shafts. Therefore load-sensing control, which reduces the non load-holding control volume pressure to 20 bar when the grabber is inactive, is developed. This is successful at reducing system pressures, but not motor drive shaft torques. It is concluded that the integration of low power auxiliary functions does not represent a significant disturbance to this electro-hydraulic variablespeed drive network, further demonstrating the potential of these networks in improving the efficiency and reducing the cost of traditional hydraulic systems.
Keywords
Documents
Colophon: This page is part of the AAU Student Projects portal, which is run by Aalborg University. Here, you can find and download publicly available bachelor's theses and master's projects from across the university dating from 2008 onwards. Student projects from before 2008 are available in printed form at Aalborg University Library.
If you have any questions about AAU Student Projects or the research registration, dissemination and analysis at Aalborg University, please feel free to contact the VBN team. You can also find more information in the AAU Student Projects FAQs.