FORM 2
THE PATENTS ACT, 1970
(39 of 1970)

&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
[See section 10, Rule 13]
WIND TURBINE NACELLE COVER ASSEMBLY;
SUZLON ENERGY LTD., A
CORPORATION ORGANISED AND EXISTING UNDER THE LAWS OF INDIA WHOSE ADDRESS IS ONE EARTH, OPP MAGARPATTA CITY, HADAPSAR, PUNE -411028, MAHARASHTRA, INDIA
THE FOLLOWING SPECIFICATION
PARTICULARLY DESCRIBES THE
INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED.

FIELD OF THE INVENTION
The invention relates to wind turbines, and more particularly to a nacelle cover assembly of wind turbines. BACKGROUND OF THE INVENTION
Generally, nacelle is equipment which is generally referred to as a Wind Turbine Generator (WTG). It is an assembly of components intended for converting wind driven kinetic energy into electrical energy, consisting of the Rotor Shaft, Main Bearing, Gearbox, Generator, Electrical Control Panel and other equipments.
During normal operation of the WTG, it is mounted on a steel tower at heights ranging from 50 meters to 160 meters from the ground. The Nacelle is enveloped/housed by an outer protective cover made from metals or composites, completely encasing all the parts within. This cover is called the "Nacelle Cover". The covering is typically aerodynamically shaped. The weight of a WTG ranges from 52 Metric Tons to 90 Metric Tons.
The design of the Nacelle Cover involves the Modular Panel Design, the joining methods and the geometry of these. The current art employs a monolithic construction of nacelle cover, with two or more large-sized sub-components for each Nacelle Cover. The parts in the current art are manufactured using hand-layup and foil infusion methods. However, such components are very large and heavy due to monolithic construction of the nacelle cover and are, therefore, difficult to handle as well as transport. Since these components are not inter-changeable, the lead time for replacement, in the event of damage at site, is high. In the current art, the cost of shipping also increases due to the monolithic construction of large-sized components.

Complex production processes, variable load specifications and laminate specifications result in high NCR of non-uniformity, in the manufacture of these components. Further, existing modular Nacelle Cover designs are made of numerous dissimilar components, numbering from 2 to 24 unique parts and, during the construction of the Nacelle Cover, these components are drilled through and connected using bolts which is not able to make the connection water-proof. Such connectors are visible from outside which does not help with aesthetically too.
There is a need for a method of constructing Nacelle Covers which overcomes the disadvantages of current art listed above. SUMMARY OF THE INVENTION
Accordingly, the present invention in one aspect provides a wind turbine nacelle cover assembly comprising a framework having a plurality of frames, a plurality of side panels, configured to be adapted between the frames, a plurality of corner panels configured to be positioned between the frames, and a sealant layer for sealing the panels. Each frame comprises a base support member, left and right support members, a top support member and corner support members, each support member interconnected to form the frame. Each side panel has a flange edge of a c-profile configuration at each side for overlapping with a flange edge of adjacent panel on the support members of the framework and each comer panel having a flange edge of a c-profile configuration at each side for overlapping with side panels and a flange edge of adjacent corner panel on support members of the framework. The sealant layer is provided between overlapping flanges of the panel. Advantageously the flange edges mating on support members of the framework are coupled from inside of the framework.

BRIEF DESCRIPTION OF THE DRAWINGS
Reference will be made to embodiments of the invention, examples of which may be illustrated in the accompanying figures. These figures are intended to be illustrative, not limiting. Although the invention is generally described in the context of these embodiments, it should be understood that it is not intended to limit the scope of the invention to these particular embodiments.
Figure 1 shows a wind turbine nacelle cover assembly in accordance with an
embodiment of the invention.
Figure 2 shows a framework for the wind turbine nacelle cover assembly in
accordance with an embodiment of the invention.
Figure 3 shows panels of the wind turbine nacelle cover assembly in
accordance with an embodiment of the invention.
Figure 4 shows coupled panels of the wind turbine nacelle cover assembly in
accordance with an embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides an assembly for a nacelle of a wind turbine generator, wherein the assembly is modular achieving modularity of 100% surface area.
Figure 1 shows a wind turbine nacelle cover assembly 100 in accordance with an embodiment of the invention. Nacelle cover assembly 100 comprises of a framework 110 (shown in detail in figure 2) and a plurality of side panels 102 and a plurality of corner panels 104.
Framework 110 as shown in figure 2 comprises of a plurality of frames 112. Each frame 112 has a base support member 114, a left support member 116, a right support member 118 a top support member 120, and corner members 122. Each

support member is interconnected to corner members 122 to form frame 112. The support members are held together by a tube 124 running parallel to framework 110 from front to rear of framework 110. According to the present invention, framework 110 is a combination of steel and fiber reinforced polymer. According to the present invention each frame 112 is made of metal, and base support member 114, left and right support member 118, and top support member 120 are formed by forming fiber reinforced polymer layer over the metal frame 112 to receive C- profile of side panels 102.
According to the present invention, side panels 102 and comer panels 104 are positioned between the support members of frame 112. In an embodiment of the present invention, all side panels 102 are identical and all corner panels 104 are identical. Side panels 102 and corner panels 104, each have a flange edge 106 on all sides of the panel. Flange edge 106 is shown in details in figure 3. Flange edge 106 as shown in the figure has a c-profile configuration, and is along length of the panel. According to the present invention, opposing sides have an upper c-profile and a lower c-profile configuration. Flange edge 106 of side panels 102 overlaps with an adjacent side panel on support members of framework 110 and further flange edge 106 of corner panels 104 overlaps with adjacent side panels 102, and adjacent corner panels 104 on support members of framework 110, enabling adjacent side panels 102 and corner panels 104 to be coupled. Coupled panels 102, 104 shown in figure 4 are held together by a suitable bolt(s) 400 from inside of framework 110. Also, a sealant layer is provided between overlapping flanges of the panel. Before overlapping panels 102, 104, the sealant layer is applied on flange 106 having lower c-profile. The sealant layer has a thickness between the range of 3mm to 10mm. According to preferable embodiment of the present invention the sealant layer used is a marine grade sealant, thus weather proofing the assembly and protecting nacelle interior from effects of

weather. Advantageously, coupling the panels by using the sealant layer and, bolting them from inside of framework 110, does not require drilling of holes for bolting of the panels from outside, thus water-proofing nacelle cover assembly 100 by interlock of the panels and by not having through drilling of holes for the bolting of the panels.
Further, flange 106 of at-least one of the panels 102, 104 has an embedded metal strip 108. As shown in figure 3 flange 106 having upper c-profile has an embedded metal strip 108 along length of flange 106. Embedded metal strip 108 provides further reinforcement to the nacelle.
According to the present invention, panels are made of fiber reinforced polymer from a single mould by using Resin Transfer Molding (RTM) method. Advantageously, all panels manufactured using RTM method will be uniform, and use of single mould simplifies replacement of the panels, if required. Also, the panels can be made by hand-layup and foil infusion methods.
Advantageously, wind turbine nacelle cover assembly of the present invention, is easily and economically transportable, as each panel is relatively smaller in size compared to the monolithic designs and there are fewer unique panels, enhancing shipping efficiency and reduction of shipping costs by achieving maximum loading capacity in standard shipping containers
The present invention is in accordance and compliance with the safety regulations of Germaneisher Lloyd Guidelines 2010 for Wind Turbine Generators
While the present invention has been described with respect to certain embodiments, it will be apparent to those skilled in the art that various changes and modification may be made without departing from the scope of the invention as defined in the following claims.

WE CLAIM:
1. A wind turbine nacelle cover assembly comprising:
a framework having a plurality of frames, each frame having a base support member, left and right support members, a top support member and corner members, each support member interconnected to the corner members to form the frame;
a plurality of side panels, configured to be positioned between the support members of the frame, each side panef having a flange edge of a c-profile configuration for overlapping with a flange edge of adjacent panel on the support members of the framework;
a plurality of comer panels configured to be positioned between the support members of the frame, each corner panei having a flange edge of a c-profile configuration for overlapping with side panels and a flange edge of adjacent corner panel on support members of the framework; and
a sealant layer provided between overlapping flanges of the panel;
wherein the flange edges mating on support members of the framework are coupled from inside of the framework.
2. The assembly as claimed in claim 1, wherein the one of the edges of adjacent panels have an upper c-profile and the other has a lower c-profile configuration.
3. The assembly as claimed in claim 1, wherein at-least one of the flanges have an embedded metal strip.
4. The assembly as claimed in claim 2 or 3, wherein the panel having the upper c-profile has the embedded metal strip.
5. The assembly as claimed in claim 1, wherein each side panel is identical.
6. The assembly as claimed in claim 1, wherein each corner panel is identical.

7. The assembly as claimed in claim 1, wherein the panels are made of fiber reinforced polymer.
8. The assembly as claimed in claim 1, wherein the frame is made of metal and the base support member, the left and right support members, and the top support member of the frame are formed by forming fiber reinforced polymer layer over the metal frame to receive C- profile of the side panels..
9. The assembly as claimed in claim 1, wherein the base support member, the left and right support member and the top support member are made of fiber reinforced polymer.
10. The assembly as claimed in claim 1 wherein the sealant layer has a thickness between the range of 3mm to 10mm