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Advanced permanent-magnet generator for gearless wind turbines


Objectives of the Project

The objective of this industrial research project is to design, manufacture and test an extremely silent, efficient and reliable 1.5 MW direct-drive generator system for gearless wind turbines. A prototype of the generator, the electronic power converter and a suitable turbine nacelle will be developed within this project. Details of the technical objectives are: Extremely low noise level, especially at partial load
High partial load efficiency at low cost
Compact, light and attractive outer design of generator and turbine nacelle Capability to support weak grids by an advanced converter control concept Long-life and totally-enclosed generator design with maximum reliability.
Technical Approach

These objectives will be achieved by successful completion of the following tasks:
Definition of requirements
Calculations of generator and converter electromagnetics / supporting structure and nacelle mechanics
Overall optimisation of generator system
Prototype manufacturing of generator, power converter and turbine nacelle Laboratory test of generator system
Field test of generator system integrated into an existing wind turbine Technical and economical evaluation.

Expected Achievements

The innovative aspects of the project may be summarized as follows: Avoiding the gearbox and applying an advanced rectifier control concept together with low rotor speed will lead to a distinctive decrease of the present noise level at low wind speeds.
Compared to other direct-drive turbines, the partial-load efficiency will be enlarged by more than 5 % and the generator diameter will be reduced by 40 %, both due to permanent-magnet excitation and advanced rectifier control; the wind turbine tower head weight will be reduced by 30 % due to the innovative bearing concept.
Compared to doubly-fed induction generator technology, the partial-load efficiency will be enlarged by more than 5 % due to the omission of gearbox and circulating power; avoiding gearbox, sliprings and brushes will permit a reduction of maintenance cost of about 20 %.
Avoiding the gearbox together with the modular composition of the power converter and the totally enclosed generator design will raise the turbine's availability to more than 99.5 %.

Funding Scheme

CSC - Cost-sharing contracts


Technische Hochschule Darmstadt
64283 Darmstadt

Participants (3)

ELIN EBG Motoren GmbH
76,Penzinger Strasse
1140 Wien
1,Technoparkstrasse 1
8005 Zurich
Lagerwey Windturbine BV

3770 AG Barneveld