Date of Award

2025

Document Type

Open Access Master's Thesis

Degree Name

Master of Science in Mechanical Engineering (MS)

Administrative Home Department

Department of Mechanical and Aerospace Engineering

Advisor 1

Wayne Weaver

Committee Member 1

Gordon Parker

Committee Member 2

Shangyan Zou

Abstract

With increased focus on wave energy converters that produce power in multiple degrees of motion, more tools are necessary to understand the behavior of these devices and cause them to reach critical resonance points. This thesis uses Floquet theory and a numerical solver to understand how a WEC of given parameters operating in surge, heave and pitch may approach points of instability using feedback control schemes. It finds that a WEC reaches these resonance points when the surge and pitch motions are driven to resonate at either the same frequency as the heave motion, or at half this frequency. This thesis then shows how to reach these resonance locations through physical design, minimizing the necessary control force for a cylindrical buoy by selecting the physical parameters to make the WEC behave as desired with minimal control input. It gives expressions to determine the design parameters of a buoy that resonates at these locations without a proportional control force, and compares the power requirements of such systems with those that require a proportional control force. This thesis shows that WECs which are designed to naturally resonate at points of linear resonance without an applied control force require significantly less energy storage on-site and smaller control actuators to drive them to resonance points than comparable designs which do.

Creative Commons License

Creative Commons Attribution-Share Alike 4.0 License
This work is licensed under a Creative Commons Attribution-Share Alike 4.0 License.

Share

COinS