Ant Colony for optimal design of PM synchronous generator for direct-drive wind turbines

In this paper, an optimal design procedure of radial surface permanent-magnet generator (PMSG) with an outer rotor for wind energy application is investigated. Firstly, an analytical model based on the resolution of the Maxwell´s equations using the separation of variable method is presented. From the same model analytical expressions of four constraint functions dedicated for the optimal design of the PMSG are developed. These constraints are: electromagnetic torque, electromotive force (EMF), flux density saturation in stator/rotor yoke and saturation in stator tooth. The Ant Colony Optimization (ACO) method is then employed to optimize two objective functions (weight and power loss of the generator) with the respect of the above mentioned constraints. Finally, the finite element method is used to validate the designed PMSG.