Electrical design for a wave buoy

Abstract

Renewable energies have been taking an important role in the disperse generation in the last years. A new renewable energy is the wave power, that transports energy by ocean surface waves, and capture that energy to do useful work. In this project is studied, discussed and designed the electrical parts needed to transform the wave power into electrical power as the control of the buoy (reactive and latching control), system (electrical or hydraulic), generators (linear or rotating),converter systems (depending on generator, speed control and grid), grid connections and transmissions systems, cables and transformers. The material produced in this report is definitely the beginning of new knowledge which can be deeply developed. From these studies some conclusions can be done as electrical systems offer excellent prospects for superior performance and other benefits compared with hydraulic systems, and the development of electrical system prototypes is justified. Phase control avoids the drawback of high power peaks keeping the advantage of increased power extraction. The rotating generation is preferred against a linear electric power generation in terms of efficiency and cost. In a plant, the wave energy converters (base units) can be connected in larger arrays ranging from tenths up to thousands of individual converters. The connections of these converters to the grid can be implemented in various ways (converters and transformer offshore or onshore and connections cables schemes) depending on the size of the farm and the proximity to the grid among other criteria as availability or cost. Taking into account cable losses and complexity the better option is place these devices onshore for small farms close to the grid and offshore for medium to large farms. Comparing connection schemes in terms of cable cost, both material and installation, and availability, systems with clusters and subclusters (small amount of base units) and one cable to the shore are the better options.