Linear analysis of a gyroscopic wave energy converter: absorbing half of the wave energy over broadband frequencies

Abstract

We present a theoretical analysis of a gyroscopic wave energy converter (GWEC), which generates electricity via the precession induced by the flywheel’s rotation and the pitch motion of a floating body. The coupled wave–body–gyroscope interaction problem is formulated under the assumptions of linear waves and resulting linear motions of both the floating body and the gyroscope. Within this framework, we identify the optimal control parameters that maximise the energy absorption efficiency. The analysis reveals that the GWEC can theoretically achieve the maximum energy absorption efficiency of 1/2 at any wave frequency through appropriate tuning of the flywheel’s rotational speed and the generator parameters. The derived theory is verified through numerical simulations in both the frequency and time domains. Furthermore, time-domain simulations incorporating the nonlinear gyroscopic response are conducted to assess the limitations of the linear gyroscopic model. These findings provide valuable insights for the future design of wave energy harvesting technologies.