ABSTRACT
As a renewable energy source, wave energy has attracted wide attentions in recent years and different wave energy converters (WECs) have been developed. To improve the energy absorption efficiency, this paper explores a novel two-degree-of-freedom (2DoF) bistable WEC based on the 1DoF bistable power take off (PTO) system. The 2DoF bistable power capture system is realized by two symmetrically oblique main springs (responsible for bistable characteristics) and an auxiliary spring (responsible for adjusting the dynamic response of the floater). The auxiliary spring, which is attached to a mass block with an additional vertical motion DoF, makes it easy for capturing more wave energy of 2DoF bistable systems in the low and high frequency regions. The effects of the damping coefficient of PTO system, nonlinear parameter, the stiffness of main spring and auxiliary spring on the power capture performance of the 2DoF bistable system are discussed based on the numerical results.
