This study examined the effects of buoy shape and Nonlinear Froude-Krylov force (NFK) on a heaving-buoy-type Wave Energy Converter (WEC). Based on the Maclaurin expansion, the theoretical solutions of the NFK were derived for three different buoy shapes; hemispheric buoy, circular vertical cylinder, and truncated conical cylinder. A hydraulic power take-off system was adopted, and the latching control strategy was applied to maximize the extracted power from the WEC. The nonlinear effects of the Froude-Krylov force and restoring force on the heaving point absorber were investigated by comparing the heave Response Amplitude Operator (RAO) and time-averaged power extraction. The results showed that the conventional linear analyses were overestimated by up to 50% under the high amplitude wave condition. The latching control strategy was the most effective when peak wave period of regular or irregular wave was 0.4–0.45 times the heave natural period of the buoy.

这项研究检查了浮标形状和非线性Froude-Krylov力（NFK）对沉浮型波能转换器（WEC）的影响。基于Maclaurin展开，得出了三种不同浮标形状的NFK的理论解。半球形浮标，圆形垂直圆柱和截头圆锥形圆柱。采用了液压动力输出系统，并采用了闭锁控制策略以最大程度地从WEC中提取动力。通过比较升沉响应振幅算子（RAO）和时间平均功率提取，研究了Froude-Krylov力和恢复力对升沉点吸收器的非线性影响。结果表明，在高振幅波条件下，常规线性分析被高估了多达50％。