Abstract
CCell is a type of Oscillating Surge Wave Energy Converter (OSWEC) under development by Zyba Renewables Ltd. Laboratory scale wave tank tests have been conducted with a prototype device equipped with a passive controllable hydraulic power take-off system. The results are used to derive a simplified semi-analytical model of the governing hydrodynamics, providing a basis for simulation studies of control algorithms. The Simple and Effective control strategy of Fusco and Ringwood (2013) is used to generate an angular velocity trajectory designed to maximise energy capture whilst keeping the device motion within physical displacement constraints. Velocity tracking is achieved using a State Feedback Control architecture with integral action (SFCIA), combined with an integral position controller acting on measured angular position in order to reduce drift effects. Good performance when subjected to scaled real irregular sea states is observed in terms of energy capture and motion, and good robustness to parameter variation is demonstrated.