The paper describes the use of a novel
permanent-magnet synchronous generator for use
with a wind turbine. The small pole pitch of the
generator allows it to operate at low speeds, be
directly coupled to the wind turbine and maintain
a direct electrical grid connection. The ability to
couple the generator directly to the wind turbine
eliminates the need for the usual gearbox, but
leads to a generator design where conventional
damper windings are ineffective as there is too
little space. The paper describes an alternative
damping system whereby the stator is allowed
limited rotational movement by connecting it to
the wind turbine housing via a spring and a
mechanical damper. This arrangement allows
greater damping of power-angle oscillations than
is possible using conventional damper windings.
The response of the generator to step changes in
driving torque is used to illustrate the
effectiveness of such a design. The behaviour of
the generator on both synchronisation and during
operation in a varying wind is discussed to
demonstrate the feasibility of this new design