Research on a double float system for direct drive wave power conversion

Abstract

The development and reasonable utilisation of wave energy have great realistic significance for solving environment pollution and energy crisis. A direct-drive system with no middle conversion devices such as gear and turbine, which has a simple structure and good stability, is widely applied to wave power systems. First, the study analysed the structure of a tubular permanent magnet linear generator. The structure of short primary and long secondary is chosen for wave power systems because of the convenience of installation and higher power density. Then, based on finite-element analysis, the structure of the generator is optimised by parametric analysis and genetic algorithm. A prototype is manufactured according to the optimised size, and the electromagnetic parameters are measured to verify the accuracy of simulation. Finally, a double floating direct-drive wave power system is installed in the port of Lian Yungang, China, and the system is tested by still and dynamic water; the results show that the system can effectively convert wave energy into electricity.