Linear PM generator for wave energy conversion in the AWS

The Archimedes Wave Swing (AWS) is a system which converts ocean wave energy into electric energy. It is planned to install a pilot plant of the AWS at the coast of Portugal to prove the survivability of the system. The AWS is an air-filled chamber of which the lid is moved up and down by the waves. This paper focusses on the energy yield and the generator system. From the linear motion, energy is extracted by means of a linear permanent-magnet (PM) generator, the design of which is described. The generator is connected to the utility grid via an umbilical and a voltage source inverter. The peak power of the system is 4MW. From the wave distribution, the annual energy yield is calculated as 2.1 GWh. To make the system economically viable, the stroke and the diameter must be increased.