Research and Development of the Utility Scale, Tocardo T4 Tidal Turbine

QED Naval和Tocardo涡轮机已经成功地部署了一个小型潮汐能装置。他们的Gen 01Subhub设备有三台发电机，设计用于社区规模的项目（总功率为150千瓦- 300千瓦），但目标是发展工业规模（总功率为300千瓦- 1.25兆瓦）和公用事业规模（总功率为2兆瓦- 4兆瓦）。这个公用事业规模的装置预计有多台发电机，每台额定功率约为1兆瓦。这个项目涉及这个发电机的开发。Tocardo的经验是在永磁同步电机（pmms），这与风能和潮汐能行业的更广泛定位相匹配。这些机器通常是直接驱动的，因此需要开发高扭矩（所谓的扭矩发动机）。由于永磁同步电机的转矩与定子绕组中的电流有关，因此电机中的转矩限制通常是由热限制引起的。因此，能够提供更高热性能的机器将能够产生更高的最大扭矩，这对于该应用来说可能能够在更高流速下磁场减弱之前改善能量捕获。因此，Tocardo已经完成了所谓的“开核机舱”拓扑结构的初步设计工作，见图1。这将取代固体转子轴与管道，允许海水自由流动通过涡轮机。这将为冷却创造一个额外的表面，提高热性能，而不需要淹没机舱，或安装主动冷却组件。后两者都带来了操作上的挑战，这在潮汐领域是需要避免的。因此，该项目的目的是评估在这种拓扑结构中电机的设计，并通过使用热建模来评估开芯机舱拓扑结构的有效性。目的是在项目结束时设计出兆瓦级潮汐涡轮机。根据建模的结果，这种设计可能采用开放式机舱概念，也可能是针对潮汐环境优化的更传统的永磁同步电动机。最后，在项目过程中，设计工具和流程将被评估，目的是提高Tocardo的设计能力。

QED Naval and Tocardo turbines have successfully deployed a small scale tidal energy device. Their Gen 01Subhub device has three generators and is designed for community scale projects (150 kW - 300 kW total), butthe ambition is to develop industrial scale (300 kW - 1.25 MW total), and utility scale (2 MW - 4 MW total).The utility scale device is expected to have multiple generators, each with a rated power of approximately 1 MW.This project concerns the development of this generator.Tocardo's experience is in Permanent Magnet Synchronous Machines (PMSMs), which matches the wideralignment of the wind and tidal industry. These machines are typically directly driven, and as such need todevelop high torques (so-called torque engines). Given the torque of a PMSM is linked to the current in statorwindings, thermal limits are usually the cause of torque limits in an electrical machine. As such, a machine thatcould deliver greater thermal performance would be able to develop a higher maximum torque, which for thisapplication may be able to improve energy capture before field weakening at higher flow rates.As such Tocardo has done preliminary design work for a so-called "open-core nacelle" topology, see Fig. 1. Thiswould replace the solid rotor shaft with a pipe, allowing sea water to flow freely through the turbine. This wouldcreate an extra surface for cooling, improving the thermal performance without the need for flooding the nacelle,or the installation of active cooling of the components. Both of the latter present operational challenges, whichin the tidal sector is something to be avoided.As such, the aim of this project is to assess the design of the electrical machine within such a topology, and toassess the effectiveness of the open-core nacelle topology through the use of thermal modelling. The aim is thatat the conclusion of the project a design for a MW scale tidal turbine will have been created. Depending on theoutcomes of the modelling this design may feature the open-core nacelle concept or may be a more conventionalPMSM optimised for the tidal environment. Finally, over the course of the project design tools and processeswill be assessed with the aim of improving Tocardo's design capabilities.