Abstract: A wind turbine with at least one blade having a pitch axis that is offset laterally so that the blade does not intersect with an axis of rotation of the wind turbine, and a center of mass and an aerodynamic center are offset from the pitch axis in the direction parallel to the axis of rotation of the wind turbine. The blade is arranged so that the blade can pitch towards stall against the action of a resilient device and also so that the centrifugal loading on at least one of the blade and one or more components optionally attached to the blade, acts against the spring in a direction to shed power by pitching the blade towards stall and also so that the torque loading provided by a power conversion device acts to pitch the blade in the opposite direction, so as to reduce the amount of load shedding whenever the power is being extracted from the wind turbine.

Abstract: A permanent magnet electrical machine comprises a first substantially planar member (9, 10) and a second substantially planar member (3) arranged substantially parallel to the first substantially planar member. The first and second members are rotatable relative to each other about a common axis substantially perpendicular to the planes of the first and second members. The first member (9, 10) is provided with an annular array of permanent magnets (7, 8) coaxial with the common axis and configured to provide a substantially axial magnetic field passing through the second member. The second member (3) is provided with a first annular array of flat coils (1) coaxial with the common axis and arranged substantially side-by-side in a first layer and with a second annular array of flat coils (2) coaxial with the common axis and arranged substantially side-by-side in a second layer. The coils (2) of the second array are offset in a circumferential direction relative to the coils (1) of the first array.