Abstract: The present invention relates to a transformer (100) for the transfer of electrical power from a nacelle (250) of a horizontal-axis wind turbine to a turbine tower (350) of said wind turbine whereby the nacelle (250) is in revolute attachment to the tower (350), comprising: a primary winding (200) adapted for attachment to the nacelle (250), and a secondary winding (300) adapted for attachment to the turbine tower (350), which windings (200, 300) are in revolute alignment with each other, and configured for transfer of electrical power by induction from the primary winding (200) to the secondary winding (300). It also relates to a method for assembly or disassembly of a wind turbine.

Abstract: The invention describes a method for maximum power point tracking approximation and speed control of a wind turbine using an AC-DC converter consisting of “passive” components only. The proposed system only uses passive electrical components or semiconductors such as inductors, capacitor or diodes. In the proposed concept this is done by designing an electric circuit so that it loads the generator output in such a way as to realize a pre-defined torque-frequency characteristic. By carefully choosing the values of the different components, the circuit can be tuned to fit an ideal torque-frequency curve. This torque characteristic is close to the maximum-power tracking control law up to the rated rotor speed, and steeply rises beyond that speed in order to maintain the rotor speed within a certain range and prevent turbine runaway.