Harvesting Ocean Wave Energy: A Proposed System for Conversion Into Electrical Power

Energy resources of offshore wind and ocean wave are clean, renewable and abundant. Various technologies have been developed to utilize the two kinds of energy separately. This paper presents the principle of an integrated generation unit for offshore wind power and ocean wave energy. The principle of the unit includes that: The wind rotor with retractable blades and the 3-DOF (degrees of freedom) mechanism with the hemispherical oscillating body are used to collect the irregular wind and wave power, respectively; The energy conversion devices (ECDs) are utilized to convert mechanical energy from both the wind rotor and the 3-DOF mechanism into hydraulic energy; The hydraulic energy is used to drive the hydraulic motors and electrical generators to produce electricity. Some analyses and experiments of the unit is conducted.

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

Energies ◽

10.3390/en14040920 ◽

2021 ◽

Vol 14 (4) ◽

pp. 920

Author(s):

Yue Hong ◽

Irina Temiz ◽

Jianfei Pan ◽

Mikael Eriksson ◽

Cecilia Boström

Keyword(s):

Wave Energy ◽

Energy Production ◽

Full Range ◽

Electrical Power ◽

Damping Coefficient ◽

Irregular Wave ◽

Ocean Wave Energy ◽

Optimal Damping ◽

The Impact

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.

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Whisk-inspired Motion Converter for Ocean Wave Energy Harvesting

IEEE/ASME Transactions on Mechatronics ◽

10.1109/tmech.2021.3093939 ◽

2021 ◽

pp. 1-1

Author(s):

Qiqi Pan ◽

Biao Wang ◽

Lingling Zhang ◽

Zhongjie Li ◽

Zhengbao Yang

Keyword(s):

Energy Harvesting ◽

Wave Energy ◽

Ocean Wave ◽

Ocean Wave Energy

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