Mechanical and structural design

Up to now, research activities on the field of direct-drive wind generators focused on the generator active part. However, cost estimations show that a considerable amount of the total generator cost is covered by its inactive part: the generator supporting structure. This is the reason for drawing attention to this so far neglected field by wind-direct engineers. Structural calculations for determining the stress and strain distribution of components of any geometry have been the first applications for Finite-Element-Methods (FEM).

direct-drive wind generators

From the standpoint of the generator designer, the main reason for investigating the generator structures is to get figures for the minimum possible airgap length for a certain design: which airgap can be realized at which structure mass? Usually, there are 3 kind of acting loads which are influencing the airgap: magnetic pull, magnetic torque and deformations due to aerodynamic loads. The magnetic loads as a function of actual airgap and current are computed with the non-linear electromagnetic FEM software package FEMAG.

possible generator supporting structure - bearing configurations

wind-direct offers the flowing services on the mechanical area:
  •  Design of suitable supporting structures
  •  FE analysis of deformations under magnetic loads
  •  Choice of optimum designs w.r.t. production boundaries