The Speed-Sensorless Control For Linear Generator Based WECS

Renewable energy sources like wind, solar and oceans renewables, gain an increasing attention due to the limited nature of fossil fuel supplies, national requirements for security of supply, as well as political pressure toward the reduction of carbon emissions and use renewable energy as it is clean and will never run out. Recently, Wave Energy Conversion System (WECS) gains an increasing attention. There are many methods for capturing energy from wave and convert it to electrical energy. Mechanical interface such as Oscillating Water Column (OWC), water turbines, and hydraulic systems are used to convert the linear motion to rotational and hence conventional rotary electrical machines such as induction or synchronous generators can be used to generate electricity. However, the main drawbacks of these Wave Energy Conversion Systems (WECS) are their mechanical complexity and low energy-conversion efficiency. Alternatively, direct-drive WECS, which is based on linear generator connected directly to a buoy, eliminates the need for complex mechanical interface.