Performance of Closely Spaced Point Absorbers with Constrained Floater Motion

The performance of a wave energy converter array of twelve heaving point absorbers has been assessed numerically in a frequency domain model. Each point absorber is assumed to have its own linear power take-off. The impact of slamming, stroke and force restrictions on the power absorption is evaluated and optimal power take-off parameters are determined. For multiple bodies optimal control parameters are not only dependent on the incoming waves, but also on the position and behaviour of the other buoys. Applying the optimal control values for one buoy to multiple closely spaced buoys results in a suboptimal solution, as will be illustrated. Other ways to determine the power take-off parameters are diagonal optimization and individual optimization. The latter method is found to increase the power absorption with about 14% compared to diagonal optimization.