Damping Studies on PMLG-Based Wave Energy Converter under Oceanic Wave Climates

Abstract

Wave energy converters (WECs), which are designed to harvest ocean wave energy, have recently been improved by the installation of numerous conversion mechanisms; however, it is still difficult to find an appropriate method that can compromise between strong environmental impact and robust performance by transforming irregular wave energy into stable electrical power. To solve this problem, an investigation into the impact of varied wave conditions on the dynamics of WECs and to determine an optimal factor for WECs to comply with long-term impacts was performed. In this work, we researched the performance of WECs influenced by wave climates. We used a permanent magnet linear generator (PMLG)-based WEC that was invented at Uppsala University. The damping effect was first studied with a PMLG-type WEC. Then, a group of sea states was selected to investigate their impact on the power production of the WEC. Two research sites were chosen to investigate the WEC’s annual energy production as well as a study on the optimal damping coefficient impact. In addition, we compared the WEC’s energy production between optimal damping and constant damping under a full range of sea states at both sites. Our results show that there is an optimal damping coefficient that can achieve the WEC’s maximum power output. For the chosen research sites, only a few optimal damping coefficients were able to contribute over 90% of the WEC’s annual energy production. In light of the comparison between optimal and constant damping, we conclude that, for specific regions, constant damping might be a better choice for WECs to optimize long-term energy production.

Quantitative Power Flow Characterization of Energy Harvesting Shock Absorbers by Considering Motion Bifurcation

“…P in = P md + P gd + P mi + P gi + P ge = P md + P gd + P mi + P gi + P etot = P md + P gd + P mi + P gi + P el + P eout (16) where P in = power of total damping force; P md = equivalent power of MMR dissipation damping force; P gd = equivalent power of gearbox and generator dissipation damping force; P mi = power of MMR inertia force; P gi = power of gearbox and generator inertia force; P ge = power of electromagnetic damping force; P etot = gross output power; P el = power of copper coil loss; and P eout = output power. Figure 6 shows the power flow in disengagement behavior.…”

“…The mechanical electromagnetic method is also referred to as an energy harvesting shock absorber (EHSA) [14].EHSAs have two types. These are often classified as linear and rotational EHSAs, also referred to as direct-drive [1,15,16] and indirect-drive EHSA models [17]. In linear EHSAs, the linear movement is utilized to turn the mechanical energy into electric energy.…”

Designing a Sea Wave Simulator to Determine the Energy Potential of a Marine Wave Power Plant Using IMU GY-86 Sensor

“…The conversion of ocean wave energy will produce maximum power, if you know the characteristics of ocean waves that can be utilized as electrical energy. Among the advantages of ocean wave energy are: (1) it can be utilized, (2) it will never run out, (3) it produces no waste, (4) it contains changes in mechanical energy, (5) its kinetic energy intensity is greater than that of other renewable energy (6), and it can be predicted [2] [3].…”

Performance of Linear Generator Designs for Direct Drive Wave Energy Converter under Unidirectional Long-Crested Random Waves

“…They can be differentiated based on many criteria such as operating principle, converter motion, power take-off method, mechanical structure, placement location, etc. [19,20]. However, one good classification to summarize its development from the beginning is according to the converter motion.…”