Rim-drive marine thruster using a multiple-can induction motor

This study presents the development, analysis, manufacture and testing of a demonstrator multiple-can line-start rim-drive induction motor for use as a bi-directional electric thruster on-board a tidal stream turbine. A simple `canned´ rotor construction was used to eliminate the requirement for a conventional squirrel-cage rotor, to minimise the rotor size and weight and improve reliability, all the while providing compatibility with the sub-sea operating environment. The experimental test results on a demonstrator 30 kW rim-drive motor show good agreement with finite-element analysis predicted results.