Optimum design of a gearless wind turbine PMSG considering wind speed probability density function

This paper shows the results of an optimization strategy that takes into account the annual wind profile of a wind turbine to minimize the generator cost and maximize the energy yield. The optimally designed machine is a 3-phase permanent magnet synchronous generator with 48 poles and 30 kW for direct drive wind turbines. The energy yield is considered in the optimization method by including the cost of losses in the objective function, which is then the sum of cost of losses, cost of materials and structure costs. To show the advantages of employing this 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 this strategy results in a machine that produces more energy during its lifetime, which compensates its higher cost. Finite element analysis software is used to verify and validate the resulting machine.