This project supports CalWave and Portland State University in the development of power take offs (PTOs) for Wave Energy Converters (WECs) using a control co-design approach. CalWave and Portland State University have been selected (separately) as award recipients of Funding Opportunity Announcement (FOA) 1837, TA2 Controls and Power Take Off (PTO) Design Integration and Testing.
The project focuses on early‐stage design of PTO and control systems in parallel (control co-design approach), which has been shown to provide significant improvements in terms of performance when compared to the classical “sequential” approach, when the control system is designed after the PTO.
The project is divided in two tasks: Task 1 supports CalWave; Task 2 supports Portland State University (PSU).
The main challenge in the design of a PTO for WECs is to provide both energy storage and high degree of controllability in order to tune the device to the current sea state. The approach considered in Task 1 (CalWave) is to design an electro/hydraulic system with distributed storage that allows the implementation of an approximate impedance matching controller at high conversion efficiency. In Task 2 (PSU) the energy storage is performed by a magnetic spring and the control is implemented on an electrical generator. The magnetic spring is adjustable and it allows the WEC to be tuned and operate efficiently on a broad range of sea states. The PTO designed in Task 2 will be tested on the AquaHarmonics device at 1:50 scale (AquaHarmonics is partner in the project awarded to PSU).
