Abstract
CalWave Power Technologies UG (CPT) is developing a submerged pressure-differential wave energy converter (WEC) capable of precise load management, lowering capital costs and increasing capacity factor.
CPT is currently working towards a scaled ocean demonstration of the WEC technology.
Historically, primary testing at 1:50 scale was completed in January 2016, and limited testing at 1:20 scale was completed in August 2016 at the U.S. Navy MASK Basin. After significant redesign in 2017, CPT completed hydrodynamic system identification in Jan. 2018 at the LIR DOB with the support of Marinet2. Testing at DOB produced over 100 test cases, totalling over 20 hours of recorded data, providing a rich data set for hydrodynamic WEC characterization and feed-in to detailed PTO and PTO control design. Follow-up tank testing was conducted in August and November of 2019 with representative PTO/device controls.
CPT is interested in utilizing a winch mechanism in its WEC capable of high cycles and full system loads. Initially, this project was intended to be focused on the testing of synthetic mooring ropes. These ropes typically suffer from cyclic bend over sheave (CBOS) failures due to a high number of bending cycles causing individual rope fibers to rub against each other. After a design iteration, an HMPE webbing belt was instead selected to perform the linear to rotary power conversion with the expectation of superior CBOS performance. CPT collaborated with TTS-Innova on the selection of an appropriate HMPE webbing. This project sought to confirm the suitability of the selected belt under representative loads and a high number of cycles in preparation for the upcoming field deployment