Wind Technologies Ltd - Development and testing of a 2 MW medium-speed Brushless DFIG for wind turbines

The project aims to move the Brushless Doubly-Fed Induction Generator (Brushless DFIG)
technology from being a promising and proven concept, demonstrated on small scales, to an
optimized industrial-scale machine for multi-megawatt wind turbine applications. The new
medium-speed drivetrain concept comprising a Brushless DFIG, a fractionally rated frequency
converter and a simplified gearbox with one or two gear stages promises significantly
enhanced reliability and cost-effectiveness for both on and off-shore wind turbines. This is
particularly important for the UK to achieve its targets for 2020.
The Brushless DFIG technology is proven in concept on small scales including a 20 kW wind
turbine and most recently, a 250 kW prototype generator on test bed. However, in order to
make the generator commercially attractive, its performance must be optimized to industrial
levels and be demonstrated on a real size.
The project, which is of a high-risk nature, will study several aspects of the Brushless DFIG
including its design, operation, control and grid connection with an aim to optimize and
improve its performance for multi-MW wind turbines. A 2 MW prototype system will be built
and then tested on a test bed to verify and refine the performance and capabilities of the
technology. This will move Wind Technologies a significant step forward in its exploitation
roadmap by mitigating the high risks involved with scaling up the technology. The nonconfidential
outcomes of the project will be made available to the TSB’s Offshore TIC.