Optimum design of a high-efficiency direct-drive PMSG

The paper shows the results of an optimization strategy that takes into account the annual wind profile of a wind turbine to design a high-efficiency permanent magnet synchronous generator. The energy yield is considered in the optimization method by including the cost of losses in the objective function, which is the sum of the costs of losses, active materials and structure. The optimally designed machine is a 3-phase permanent magnet synchronous generator with 48 poles and 40 kW for direct drive wind turbines. To show the advantages of employing the proposed strategy, the results of a standard optimization strategy, which minimizes the generator costs not regarding energy production, are also presented and compared. It is shown that the difference in energy proceeds is sufficient to compensate the higher cost of the high-efficiency generator. At the end the trade-off between the PMSG efficiency and its cost is analyzed using a Pareto front.