Comparison of Cobalt-Iron and Silicon-Iron Laminations for a Wave Energy Application

This paper evaluates an electric generator manufactured of cobalt-iron laminations used for a wave energy application. The properties of the two cobalt-iron designs are compared with a reference machine, which employs conventional electric steel laminations. Operation trajectories and machine losses, as well as the annual energy production and the losses are obtained through finite element analysis. Furthermore, the investment costs are calculated and a simple life cycle cost analysis is performed. The results state that, despite the superior induction properties, the cobalt-iron results in higher losses, therefore the design variant manufactured fully of the cobalt-iron laminations have high losses throughout the operation. Strategic use of the cobalt-iron laminations only in the rotor results in decreased machine losses, however due to the high investment cost, the life cycle cost of the cobalt-iron rotor design is higher than that of the reference design.