Ean Amon

A Permanent-Magnet Tubular Linear Generator for Ocean Wave Energy Conversion

This paper presents a novel permanent-magnet tubular linear generator (PMTLG) buoy system designed to convert the linear motion of ocean waves into electrical energy. The design incorporates no working seals and a saltwater air-gap bearing surface integration between the PMTLG buoy components. The internal generator design will be discussed, in addition to the system integration with the buoy structure. The simulation and hardware results of the generator are presented.

Comparison of Direct-Drive Power Takeoff Systems for Ocean Wave Energy Applications

This paper presents a comprehensive power takeoff (PTO) analysis program conducted as a collaborative research effort between Columbia Power Technologies, Inc., Oregon State University (OSU), and the U.S. Navy. Eighteen different direct-drive technologies were evaluated analytically and down-selected to five promising designs. Each of the five prototypes was simulated, modeled in SolidWorks, and built at the 200-W peak level and tested on OSUs wave energy linear test bed. The simulations were validated with the 200-W experimental results and then scaled up to 100 kW, with full 100-kW designs including costs, maintenance, operations, etc., to estimate the cost of energy (COE) for each PTO buoy system at utility scale.

Maximum Power Point Tracking for Ocean Wave Energy Conversion

Many forms of renewable energy exist in the worlds oceans, with ocean wave energy showing great potential. However, the ocean environment presents many challenges for cost-effective renewable energy conversion, including optimal control of a wave energy converter (WEC). This paper presents a maximum power point tracking (MPPT) algorithm for control of a point absorber WEC. The algorithm and testing hardware are presented in detail, as well as simulated and laboratory test results. The results show that MPPT applied to ocean wave energy is an effective and promising control strategy.

Numerical Modeling and Ocean Testing of a Direct-Drive Wave Energy Device Utilizing a Permanent Magnet Linear Generator for Power Take-Off

For the past several years an inter-disciplinary research group at Oregon State University (OSU), working in conjunction with Columbia Power Technologies (CPT) has been researching innovative direct-drive wave energy systems. These systems simplify the conversion of wave energy into electricity by eliminating intermediate energy conversion processes. In support of this research OSU and CPT have developed a hybrid numerical/physical modeling approach utilizing a large scale linear test bed (LTB), and a commercial coupled analysis tool. This paper will present an overview of this modeling approach and its application to the design of a 10kW prototype wave energy conversion system that was tested in the open ocean in the fall of 2008. The data gathered during ocean testing was used to calibrate the numerical model of the device and predict the energy capture potential of the system.Copyright

A novel maximum power point tracking algorithm for ocean wave energy devices

Many forms of renewable energy exist in the worlds oceans, with ocean wave energy showing great potential. However, the ocean environment presents many challenges for cost-effective renewable energy conversion, including optimal control of a Wave Energy Converter (WEC). This paper presents a novel maximum power point tracking (MPPT) algorithm for control of a point absorber WEC. The algorithm and control hardware are presented in detail, as well as ocean and laboratory test results. The results show that MPPT applied to ocean wave energy is an effective and promising control strategy.

From Blue to Green [Ask the Experts]

In this issue of IEEE Control Systems Magazine we ask Ted Brekken, Belinda Batten, and Ean Amon to respond to a query on the uses of systems and control technology in wave-energy production. Ted, Belinda, and Ean are all involved in wave energy projects at Oregon State University.

A novel ocean sentinel instrumentation buoy for wave energy testing

This paper presents a novel Ocean Sentinel instrumentation buoy that the Northwest National Marine Renewable Energy Center (NNMREC) has developed with AXYS Technologies for the testing of wave energy converters (WECs). NNMREC is a Department of Energy-sponsored partnership among Oregon State University (OSU), the University of Washington (UW), and the National Renewable Energy Laboratory (NREL). The Ocean Sentinel instrumentation buoy is a surface buoy based on the 6-m NOMAD (Navy Oceanographic Meteorological Automatic Device) design. The Ocean Sentinel provides power analysis, data acquisition, and environmental monitoring, as well as an active converter interface to control power dissipation to an onboard electrical load. The WEC being tested and the instrumentation buoy are moored with approximately 125 meters separation; connected by a power and communication umbilical cable. The Ocean Sentinel was completed in 2012 and was deployed for the testing of a WEC at the NNMREC open-ocean test site, north of Newport, OR, during August and September of 2012.

Experimental Force Characterization and Numerical Modeling of a Taut-Moored Dual-Body Wave Energy Conversion System

This paper presents an innovative modeling technique that combines experimental force measurements from a full scale linear generator with a coupled model of a two body, moored floating system to investigate the performance of a wave energy conversion system. An experiment was conducted using the Oregon State University’s wave energy linear test bed to characterize the frictional and electromagnetic forces generated by the SeaBeavI linear generator. These force characteristics have been incorporated into a coupled model using a numerical fluid-structure interaction model, OrcaFlex, to predict the energy extraction potential of the system.

A Power Analysis and Data Acquisition System for Ocean Wave Energy Device Testing

In the testing of ocean wave energy devices, the demand for a portable and robust data acquisition and electrical loading system has become apparent. This paper investigates the development of an inclusive system combining loading capabilities, real-time power analysis, and data acquisition for the testing of deployed ocean wave energy devices.

Testing the WET-NZ Wave Energy Converter Using the Ocean Sentinel Instrumentation Buoy

This paper describes ocean testing of the half-scale Wave Energy Technology-New Zealand (WET-NZ) prototype wave energy converter (WEC) using the Ocean Sentinel instrumentation buoy during a 6-week deployment period in August‐October 2012. These tests were conducted by the Northwest National Marine Renewable Energy Center (NNMREC) at its Pacific Ocean test site off the coast of Newport, Oregon. The WET-NZ is the product of a research consortium between Callaghan Innovation, a New Zealand Crown Entity, and Power Projects Limited (PPL), a Wellington, New Zealand private company. The Oregon deployment was project managed by Northwest Energy Innovations (NWEI), a Portland, OR firm. NNMREC is a Department of Energy sponsored partnership between Oregon State University (OSU), the University of Washington (UW), and the National Renewable Energy Laboratory (NREL). The Ocean Sentinel instrumentation buoy is a 6-m surface buoy, developed in 2012, that provides a stand-alone electrical load, WEC generator control, and data collection for WECs being tested. The Ocean Sentinel was deployed and operated for the first time during the 2012 WET-NZ tests. During these tests, the operation of the WET-NZ was demonstrated and its performance was characterized, while also proving successful deployment and operation of the Ocean Sentinel.