Salter’s Duck can convert wave energy to mechanical energy with high efficiency up to 90%. The limitations and challenges in the usage of Salter’s Duck for energy production include preventing hydraulic system from the risk of leaking hydraulic oil and removing complex huge fixed bracket. This paper presents the conceptual design and an experimental investigation of a mechanical power-take-off (PTO) system for the floating Salter’s Duck. The PTO system is fully installed inside of the Salter’s Duck. It consists of double counter-rotating flywheels converting the bi-directional rotation of the wave energy converter into a stable unidirectional rotation that drives a rotary generator to produce electricity. The bi-to-unidirectional function is achieved through inertial wheels, thus the novel PTO system is free of large supporting structures and hydraulic cylinders. In this paper, a detailed conceptual PTO design is proposed firstly. Further, the influence of the swing amplitude and rotation period of the wave energy converter on the power extraction efficiency is investigated. Then, the influence of the electrical load on the power-extraction efficiency is researched. In the end, the effect of the speed increasing ratio on the mechanical efficiency is examined. The experimental results show that the new type of generator mechanism can produce electricity stably.

Salter's Duck可以将波能转换为机械能，效率高达90％。萨特鸭子用于能源生产的局限性和挑战包括防止液压系统泄漏液压油和移除复杂的巨大固定支架。本文介绍了浮动Salter's Duck机械动力输出（PTO）系统的概念设计和实验研究。PTO系统完全安装在Salter's Duck的内部。它由双反向旋转飞轮组成，它们将波能转换器的双向旋转转换成稳定的单向旋转，从而驱动旋转发电机发电。双向功能是通过惯性轮实现的，因此，新型PTO系统没有大型支撑结构和液压缸。本文首先提出了详细的概念取力器设计。此外，研究了波能转换器的摆幅和旋转周期对功率提取效率的影响。然后，研究了电负载对功率提取效率的影响。最后，研究了减速比对机械效率的影响。实验结果表明，新型发电机机构能够稳定地发电。研究了电负载对功率提取效率的影响。最后，研究了减速比对机械效率的影响。实验结果表明，新型发电机机构能够稳定地发电。研究了电负载对功率提取效率的影响。最后，研究了减速比对机械效率的影响。实验结果表明，新型发电机机构能够稳定地发电。