Image-empty-state.png

Wave energy convertor: High-efficient, highly robust power-take-off for wave energy converters based on electromechanical power sharing transmission

IP Status

Grant

Research Organization

Ghent University

Technology Type

Engines Or Pumps

Expires

2037

Inventors

Degrieck Joris [Be]; Van Paepegem Wim [Be]

About the technology

Researchers at Ghent University have developed an innovative PTO device which converts wave motion into a one directional rotational movement based on a so-called power-sharing or power-split transmission (PST). A power split transmission has at least three ports.
The innovative PTO is arranged between a movable element interacting with the waves (i.e. one axis is connected to one of the three ports) and a main electric generator (i.e. the second axis is connected to a second port). The device further comprises an electromechanical control means such as a variable speed auxiliary electrical machine connected to the last, i.e. the third port of the three ports of the PST. The control unit is adapted for controlling the power distribution in the power split transmission as to realize a one-way rotation of the main electric generator despite the oscillatory movement of the movable element.

Solution

Researchers at Ghent University have developed an innovative PTO device which converts wave motion into a one directional rotational movement based on a so-called power-sharing or power-split transmission (PST). A power split transmission has at least three ports.
The innovative PTO is arranged between a movable element interacting with the waves (i.e. one axis is connected to one of the three ports) and a main electric generator (i.e. the second axis is connected to a second port). The device further comprises an electromechanical control means such as a variable speed auxiliary electrical machine connected to the last, i.e. the third port of the three ports of the PST. The control unit is adapted for controlling the power distribution in the power split transmission as to realize a one-way rotation of the main electric generator despite the oscillatory movement of the movable element.

Benefits

The main advantage of the device is that a wave motion which is a movement in substantially two different directions, e.g. a substantially upward and substantially downward movement, is efficiently transferred into electrical energy. We have shown in simulation the basic potential and advantages of the technology. The main benefits are a result of the fact that the PST provides an additional degree of freedom to optimize and control the PTO. Hence:
- For a nominal seastate (SS) more electrical energy can be extracted (+25% yield for the same installed power compared to a direct drive system)

- The power quality of the produced electricity is increased (better power flatness factor)

- The PST introduces an inherent over-power protection (de-tuning of the WEC is possible)

- At several sea states, the energy yield is less sensitive to the actual settings

- In the case an EVT is used to implement the PST there is no mechanical wear. In case a
mechanical implementation is opted for, the torque levels in the PST gear box remain much acceptable.

Application Fields

PTO system for the conversion of wave energy to electrical energy. The PTO includes an PST; several implementations of the PST are feasible:
- implementation via a planetary gear box with all three axes operational.
- implementation via a differential.
- implementation through a so-called EVT (Electromechanical Variable Transmission). In
preparation of a H2020 project this has been studied in more detail and lead to the proposal of a generic versatile PTO approach for wave energy devices

About the Research Organization

I'm a paragraph. I'm connected to your collection through a dataset. Click Preview to see my content. To update me, go to the Data Manager.

arrow&v

Thanks for submitting!

About the Research Organization