Lift system mountable in a nacelle of a wind turbine

1. A lift system comprising:

a nacelle of a wind turbine;

a mounting interface removably securable to a generator in the nacelle;

a swivel rotatably and removably mounted on the mounting interface;

a hydraulic motor for operating the swivel;

a power pack comprising a hydraulic pump and an electric motor for operating the hydraulic pump, the hydraulic pump connectable to the hydraulic motor through hydraulic lines and quick connect hydraulic fittings; and,

a knuckle boom rigidly mounted on the swivel, the knuckle boom comprising an extendable boom arm, the extendable boom arm comprising a translatable boom section slidably mounted on the boom arm,

wherein the swivel is rotatable to rotate the knuckle boom mounted thereon about a vertical axis,

and wherein the power pack is mounted on the mounting interface and does not extend beyond a maximum height to permit closing the nacelle when the mounting interface is mounted on the generator and the knuckle boom is dismounted from the mounting interface.

2. The lift system of claim 1 , wherein the mounting interface comprises clamps that engage protruding elements of the generator to securely and removably mount the mounting interface on a top of the generator.

3. The lift system of claim 1 , wherein:

the swivel comprises a rotatable portion on which the knuckle boom is mounted and a fixed portion comprising a first through aperture;

the mounting interface comprises a second through aperture concentrically aligned with the first through aperture when the swivel is mounted on the mounting interface; and,

the swivel is secured to the mounting interface by a non-threaded pin removably inserted through the first and second through apertures, the removable non-threaded pin permitting mounting of the swivel on and dismounting of the swivel from the mounting interface.

4. The lift system of claim 3 , wherein the first through aperture, the second through aperture and the removable non-threaded pin comprise a plurality of first through apertures, second through apertures and removable non-threaded pins.

5. The lift system of claim 3 , wherein the mounting interface further comprises a third through aperture through which a support pin is inserted, the swivel comprising a support surface having an indent in which the support pin is engaged so that the swivel rests on the support pin when the swivel is mounted on the mounting interface.

6. The lift system of claim 5 , wherein the third through aperture and the support pin comprise a plurality of third through apertures and support pins.

7. The lift system of claim 1 , wherein the mounting interface comprises one or more hydraulic fluid reservoirs.

8. The lift system of claim 7 , wherein the one or more hydraulic fluid reservoirs is one or more hollow side rails of the mounting interface in fluid communication with a hydraulic pump mounted on the mounting interface.

9. The lift system of claim 2 , wherein the clamps comprise hooking portions that engage the protruding elements, and further comprise bolts for tightening the clamps on the generator.

10. The lift system of claim 1 , further comprising a support bracket removably mounted on the mounting interface, the support bracket adapted to securely support a control unit thereon.

11. The lift system of claim 10 , wherein the support bracket and the mounting interface comprise mated through apertures that receive removable mounting pins to mount the support bracket on the mounting interface.

12. The lift system of claim 1 , wherein the knuckle boom is able to lift an upper housing of a gearbox of the wind turbine.