Owing to the increasing penetration of renewable power generation, the modern power system faces great challenges in frequency regulations and reduced system inertia. Hence, renewable energy is expected to take over part of the frequency regulation responsibilities from the gas or hydro plants and contribute to the system inertia. In this article, we investigate the feasibility of frequency regulation by the offshore hydrostatic wind turbine (HWT). The simulation model is transformed from NREL (National Renewable Energy Laboratory) 5-MW gearbox-equipped wind turbine model within FAST (fatigue, aerodynamics, structures, and turbulence) code. With proposed coordinated control scheme and the hydrostatic transmission configuration of the HWT, the ‘continuously variable gearbox ratio’ in turbulent wind conditions can be realised to maintain the constant generator speed, so that the HWT can be connected to the grid without power converters in-between. To test the performances of the control scheme, the HWT is connected to a 5-bus grid model and operates with different frequency events. The simulation results indicate that the proposed control scheme is a promising solution for offshore HWT to participated in frequency response in the modern power system.

中文翻译：

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无变流器并网海上静压风力发电机组的可行性研究

由于可再生能源发电的日益普及，现代电力系统在频率调节和降低系统惯性方面面临着巨大的挑战。因此，可再生能源有望取代天然气或水力发电厂的部分频率调节职责，并有助于系统惯性。在本文中，我们研究了海上静压风力涡轮机（HWT）进行频率调节的可行性。该仿真模型是从FREL（疲劳，空气动力学，结构和湍流）代码中的NREL（国家可再生能源实验室）配备5兆瓦齿轮箱的风力涡轮机模型转换而来的。通过提出的协调控制方案和HWT的静液压传动配置，可以在湍流的风力条件下实现“无级变速比”，以保持恒定的发电机转速，因此HWT可以连接到电网，而无需在其间安装功率转换器。为了测试控制方案的性能，HWT连接到5总线网格模型并以不同的频率事件运行。仿真结果表明，所提出的控制方案是海上HWT参与现代电力系统频率响应的有前途的解决方案。