ROTATING ELECTRIC MACHINE WITH A STATOR WINDING COMPRISING A PLURALITY OF COILS AND METHOD FOR MANUFACTURING SAME
A rotating electric machine is provided and includes a rotor rotating around an axis, and a stator concentrically surrounding the rotor, the stator being equipped with a stator winding, which includes a plurality of coils. Each of the coils is wound in a series of adjacent single coils around a respective series of adjacent teeth distributed along the inner circumference of a laminated stator core and extending in axial direction. All of the single coils of each coil are wound in an uninterrupted fashion with one continuous cable.
1 . Rotating electric machine ( 10 ), comprising a rotor ( 11 ) rotating around an axis, and a stator ( 12 ) concentrically surrounding said rotor ( 11 ), said stator ( 12 ) being equipped with a stator winding ( 16 ), which comprises a plurality of coils ( 25 ), each of said coils ( 25 ) is wound in a series of adjacent single coils ( 25 a - d ) around a respective series of adjacent teeth ( 14 ) distributed along an inner circumference of a laminated stator core ( 13 ) and extending in axial direction, all of the single coils ( 25 a - d ) of each coil ( 25 ) are wound in an uninterrupted fashion with one continuous cable ( 17 ).
2 . Rotating electric machine according to claim 1 , wherein said cable ( 17 ) is made from several copper strands ( 18 a , 18 b , . . . , 18 x ).
3 . Rotating electric machine according to claim 2 , wherein the copper strands ( 18 a , 18 b , . . . , 18 x ) of each cable ( 17 ) have a rectangular cross section and lie parallel in the cable without being transposed, such that the thickness of the cable ( 17 ) is almost identical to a thickness of a single copper strand ( 18 a , 18 b , . . . , 18 x ).
4 . Rotating electric machine according to claim 1 , wherein the cable ( 17 ) is formed as a flat cable and wound within the single coils ( 25 a - d ), such that adjacent windings have flat sides that abut each other.
5 . Rotating electric machine according to claim 1 , wherein the single coils ( 25 a - d ) of each coil ( 25 ) each have the same number of turns.
6 . Rotating electric machine according to claim 1 , wherein adjacent single coils ( 25 a - d ) of each coil ( 25 ) are interconnected by an interconnection ( 21 ) in the form of an arched section of the cable ( 17 ) outside of the teeth ( 14 ), and within each coil ( 25 ) the interconnections ( 21 ) are placed on alternating sides of the coil ( 25 ).
7 . Rotating electric machine according to claim 1 , wherein the machine has 3, 5 or 7 phases and each of said plurality of coils ( 25 ) is assigned to one of said phases.
8 . Rotating electric machine ( 10 ) of claim 1 , wherein the machine is a multi-phase synchronous generator.
9 . Method for manufacturing a coil ( 25 ) for a rotating electric machine ( 10 ) comprising the steps of:
a) providing a flat cable ( 17 ) using a predetermined number of copper strands ( 18 a , 18 b , . . . , 18 x ) with rectangular cross section;
b) insulating the cable ( 17 ) by wrapping around an insulating tape;
c) winding with said cable ( 17 ) a first single coil ( 25 a ) on a mandrel, such that said first single coil ( 25 a ) fits on a tooth ( 14 ) of the stator ( 11 ) of the rotating electric machine ( 10 );
d) detaching the first single coil ( 25 a ) from the mandrel and turning it around without cutting the cable ( 17 );
e) winding with said cable ( 17 ) a second single coil ( 25 b ) on a mandrel, such that said second single coil ( 25 b ) fits on a tooth ( 14 ) of the stator ( 11 ) of the rotating electric machine ( 10 );
f) detaching the second single coil ( 25 b ) from the mandrel, turning it around without cutting the cable ( 17 ) and placing it aside the first single coil ( 25 a ) as the coils are arranged and interconnected in the stator ( 11 ); and
g) repeating steps (e) and (f), until all of the single coils ( 25 a - d ) of the coil ( 25 ) are wound and arranged to build said coil ( 25 ).
10 . Method according to claim 9 , wherein the coil ( 25 ) is impregnated after being wound.
11 . Method according to claim 9 , wherein the coil ( 25 ) is impregnated before being inserted into the slots ( 15 ) of the stator ( 11 ), and the interconnections ( 21 ) between adjacent single coils ( 25 a - d ) of the coil are prevented from being impregnated at that time.
12 . Method according to claim 9 , wherein the coil ( 25 ) is impregnated with all other coils of the machine after being inserted into the slots ( 15 ) of the stator ( 11 ) in a global impregnation process.