Gary Connor

Design and testing of a contra-rotating tidal current turbine

Abstract A contra-rotating marine current turbine has a number of attractive features: nearzero reactive torque on the support structure, near-zero swirl in the wake, and high relative inter-rotor rotational speeds. Modified blade element modelling theory has been used to design and predict the characteristics of such a turbine, and a model turbine and test rig have been constructed. Tests in a towing tank demonstrated the feasibility of the concept. Power coefficients were high for such a small model and in excellent agreement with predictions, confirming the accuracy of the computational modelling procedures. High-frequency blade loading data were obtained in the course of the experiments. These show the anticipated dynamic components for a contra-rotating machine. Flow visualization of the wake verified the lack of swirl behind the turbine. A larger machine is presently under construction for sea trials.

Development and In-Sea Performance Testing of a Single Point Mooring Supported Contra-Rotating Tidal Turbine

This paper discusses the development and in-sea performance testing of a single point mooring supported contra-rotating tidal turbine. It was presented at the 28th International Conference on Ocean, Offshore and Arctic Engineering in 2009.

Simulation of a radial flux permanent magnet generator with two contra-rotating rotors

In this paper, the no-load operational characteristics of radial-flux permanent magnet generators with two contra-rotating rotors are addressed. Three different radial flux machine topologies have been qualitatively studied through a sequence of stationary two dimensional finite element field solutions. It is shown that the peak value of the induced phase electromotive force during synchronous operation depend on the angular positions of the two rotors relative a fixed reference in the stator winding.