Design and Dynamic Modeling of Magnetic Power Split Device for a Tidal Stream Turbine

To further reduce the cost of tidal energy, fully rated power converter failure should be addressed. It was the leading cause of down time in the MeyGen phase 1a project. A magnetic power split device is able to offer a partially rated converter, which has increased reliability over the fully rated converter. As a novel device, understanding the design requirements and dynamic behaviour are crucial. This paper address parameters that should be considered for minimising the cost of the magnetic power split device for a given tidal turbine operating strategy. It was found that the power rating of the device can be reduced by careful selection of the pole pair combination. The dynamic modelling and control of the device are also considered. A full state feedback controller is implemented and gives good response. This demonstrates that the magnetic power split device could suitably control the turbine rotor to follow the operating strategy for maximum power extraction from the flow.