Behaviour improvement during faults of fixed speed stall control induction generator wind turbines



This paper describes a simple and economical way to improve the behaviour of a stall control wind turbine with fixed speed induction generator during faults. It proposes using the existing thyristor bridge and capacitors in combination with new resistors, to create a self-exciting system isolated from the grid during faults, controlling the terminal voltage and speed generator in order to reduce the reactive consumption and peak speed. This is possible as a result of the thyristor bridge and resistor acting as a variable load.

Dynamic simulations show that fault ride-through capability for symmetrical and asymmetrical faults of a stall wind turbine can be achieved by using this proposal. A comparison between this solution and the standard static compensator solution demonstrates that the proposed solution works better, mainly because of the absence of overspeed problems when the overspeed protection is set at around 1.04 p.u. (a typical level for these wind turbines). Copyright © 2008 John Wiley & Sons, Ltd.