Design Tool for 5-20 MW Direct Drive Generators

This paper reports on a machine design tool for large (5-10MW) direct drive electrical generator. The aim of the work is to construct a flexible calculation tool that enables the analysis of different ideas and concepts for generator design. The tool is intended for engineers that are involved in the design of wind turbine systems.
The design tool comprises calculation modules that are kept as independent as possible from each other so that new machine geometries and types can be modelled by reusing, recombining and modifying the different modules.
Choice of the most suitable candidates for the application is presented. Assessment is made based on suitability criteria combined with the SWOT analysis method.
An analytic design is generated at first; then visualised in 3D CAD, evaluated using FEM and a dynamic model simulation. An optimisation module is available for improving the design.
The calculations were validated by comparing results with literature reporting machines with similar ratings, laboratory tests on a prototype and by evaluating a given design using different software like finite element, 3D CAD and dynamic simulation programs.