1. SUMMER INTERNSHIP
PROGRAM
Suzlon Generators
manufacturing plant, Chakan
Industrial Area, Pune
13BEM0003
Vishnu Vardhan
VIT University, Vellore

2. PURPOSE
Suzlon Generators proves to be the biggest manufacturer of Wind
Turbine Generators in India and is one of the leading Energy
firms in the present global scenario. The purpose behind this
internship program is to enhance the level of understanding
towards the industrial ways of functioning and have a hands on
experience with the manufacturing processes involved in the
making of the Generator components.
The internship program involved an extensive in-
plant training where the student was acquainted with various
operational techniques and processes which will prove to be
helpful in gaining practical knowledge for the student and help
the firm produce well versed engineers for the future of
renewable energy.

3. SUBDIVISIONS IN THE
PLANT
 Lamination shop
 Core building shop
 Rotor winding shop
 Stator building shop
 VPI shop
 Assembly shop
The generator models produced by the Suzlon Plant include 2.1 Mw, 1.5
Mw and 600 Kw generators which have their own specifications for the
sizes of stators and rotors. The raw material, i.e. grade 50C400 steel with
golden yellow coating of grade C3M is supplied by a nearby Thyssen Krupp
plant.
The Suzlon generator plant consists of the following six
manufacturing shops where the rotors and stators are manufactured from the
scratch.

4. The Lamination Shop
 50C400 steel roll with a 4 micron silicon coating grade of C3M is
used for the basic lamina cutting.
 A 250 ton press, operating between .5 mm and 2 mm is used, roll is
opened and bent flat automatically, monitored using lasers.
 The flat plate is sent to the VLC programmed blanking machine
where discs of prescribed dimensions are punched out
automatically.
 The discs are sent to the workers, who place them in punching
machines and projections are cut in the disc, allowing the scope of
formation of slots for the magnetic core (in stator) and copper bars
to be inserted (in rotor).
 Two manually operated machines cut out rotor and stator sections
respectively.

5. Core Building Shop
 An “I” profile, metal rod is cut and weld together with an uncoated rotor
lamina, using spot welding machine.
 Coated rotor laminas are taken and stacked together, placing a “I” profile
welded uncoated lamina after a prescribed number of regular laminas.
 The laminas are held together using metal compression plate and kept in an
oven for 6 hours, 180° C.
 The shaft is inserted in the rotor while hot, such that, upon cooling, it firmly
clenches the material.
 Stator laminas are similarly, joined and welded together with the help of
mandrill.
 The VTL (Vertical Turning Lathe) machine performs turning operation on
the stator to remove the excess metals and any deformations.
 Filing and cleaning of the stator is done.

6. Rotor Winding Shop
 Copper flats (rectangular bars) are taken and taped with
insulating fabric coating.
 The flats are inserted in the rotor slots.
 Copper bars are manually turned into a semi spiral shape
and again insulated.
 The Cu1655 and Cu1630 flats are joined together by
interfacing with a 40% Silver strip, by Induction Brazing
process.

7. Stator Shop
 The wires are taken and manually molded into frames, by looping
process.
 Coil taping takes place, coated with polyester tape for insulation.
 Coils are stitched together, by process called ‘Stitching’.
 Lead formation is done, where a reference is made for further
processes and makes the tip of the stator.
 By the ‘Sleeving’ process, sleeves are mode on the stator modules.
 Insulation is applied by using glass taping.
 Soft core magnet bars are inserted in the stator slots, thus mounting
and wedging is accomplished.
 A double mount of Poromate is utilized for insulation between two
coils.

8. VPI (Vacuum Pressure Impregnation)
Shop
 VPI helps in reducing the vibrations and binding the
components together, reducing noise and mechanical wear.
 The stator and rotor are put and rotated in separate chambers
at low RPMs.
 A vacuum of 0.018 mBar is maintained there to avoid foreign
contaminants and air pockets.
 Resin is sprayed at a high temperature and an even coating is
obtained while rotating the rotor/stator for about 12 hours.
 Resin mixture 100:90:0.08 ratio of Resin, Hardener and
Accelerator; the resin used is EPR-162.
 The component is set to dry. This process takes about 30
hours.

9. Assembly Shop
 The Stator core insertion takes place at 140° C, for two hours.
 Vertical leveling of the module is ensured.
 Welding of the stator is done with the frame.
 Rotor balancing is done by test run at low RPMs, weights are added
in the buffer slots, if required.
 All the components are painted and well greased bearings are
inserted on both ends.
 The rotor/stator assembly is placed in a protective case.
 End shield assembly is done at both the ends.
 Slip ring, brush gear assembly is inserted on the non driving end.
 Slip ring housing is fitted for protection.
 Air cooling assembly is set up at the top of the frame.
 Speed encoder assembly is fitted on the shaft.

10. Conclusion
The Generators are shipped all across the country
with wind farms ranging from Tamil Nadu to
Maharashtra. Different wind speeds require
different dimensions and Suzlon leaves no stone
unturned in seeing that happen efficiently.
Firms like Suzlon, which promote
renewable energy technologies are a boon to nature
and are helping this world recover the tragedy
caused by fossil fuels.

11. My heartfelt thanks to the officials and the firm, which
gave me such an amazing opportunity to work and
understand the manufacturing processes involved in the
making of a Windmill generator. I aspire to work in the
field of renewables and this training would be a major
paving stone in my career.
Thanks and regards
Vishnu Vardhan
Student, B.E 2nd Year
VIT University
vishnu6895@gmail.com
A note of Thanks