The power take-off system plays a vital role in the wave energy generating unit. Here, for studying the operation characteristics and methods of the hydraulic power take-off system, its basic model is built relying on the operating principles of every component. Meanwhile, a proportional–integral–derivative (PID) controller is also designed to regulate the rotational speed of the motor. Then, a test platform for the hydraulic power take-off system is constructed to verify the correctness of the model. Fortunately, based on model analyses, some useful results are found. Firstly, the PID controller has a visible effect on stabilizing the rotational speed. In addition, a group of optimal control parameters are obtained. Secondly, the influences of the displaced volume on the operation characteristics of the hydraulic power take-off system are found. Meanwhile, the optimal displaced volume is also presented by weighing the efficiency and stability. Finally, the operation modes and regions of the hydraulic power take-off system are obtained, and its rationality is also proved by a simulated running of the system. More importantly, these results can provide a reference to the design and operation of the hydraulic power take-off system.

中文翻译：

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液压取力器系统的工作特点及方法

动力输出系统在波浪能发电机组中起着至关重要的作用。在此，为研究液压取力器系统的工作特性和方法，根据各部件的工作原理建立其基本模型。同时，还设计了比例积分微分 (PID) 控制器来调节电机的转速。然后，搭建了液压取力器系统的测试平台，验证了模型的正确性。幸运的是，基于模型分析，发现了一些有用的结果。首先，PID控制器对稳定转速有明显的效果。此外，还得到了一组最优控制参数。其次，找出了排量对液压取力器系统工作特性的影响。同时，通过权衡效率和稳定性，给出了最优排量。最后，得到了液压取力器系统的运行方式和区域，并通过系统的模拟运行证明了其合理性。更重要的是，这些结果可为液压取力器系统的设计和操作提供参考。