Electrical induction device for high-voltage applications

1. An electrical induction device for high voltage applications, comprising:

a magnetic core having at least one leg and operatively coupled to a supporting structure;

at least one inner winding which is arranged around said leg and has a first rated voltage;

at least one outer winding which is arranged around said at least one inner winding and has a second rated voltage; and

electrically insulating means;

wherein said at least one inner winding comprises a plurality of substantially concentric turns formed by a sheet of electrically conducting material which is spirally wound, and wherein said electrically insulating means comprise at least one layer of electrically insulating material which is arranged between mutually facing surfaces of said concentric turns, and first shaped insulating means which covers, at least partially, at least one of the upper and lower external rims, and external wall, of said at least one inner winding wherein said first shaped insulating means comprise a first shaped body and a second shaped body having an L-shaped cross section, said first and second shaped bodies being connected to said upper and lower external rims, respectively, with a first side which is positioned substantially parallel to said leg and covers a portion of the outer surface of the last external turn, and a second side which is positioned substantially perpendicular to said leg and covers the corresponding short side of at least said last external turn; and

wherein said at least one inner winding comprises a plurality of through channels each extending substantially parallel to said leg between two adjacent turns, the second side of said first and second shaped bodies having a length which is shorter than the distance between the outer surface of said last turn and the external wall of the most external through channel.

2. The electrical induction device according to claim 1 wherein said at least one inner winding has a first rated voltage which is lower than the second rated voltage of said outer winding.

3. The electrical induction device according to claim 1 wherein said first shaped insulating means comprise a U-shaped body which wraps, at least partially, at least one of the upper or lower tip portions of at least the last external turn.

4. The electrical induction device according to claim 3 wherein said first shaped insulating means comprise a first and a second U-shaped bodies wrapping, at least partially, the upper and lower tip portions of the last external turn, respectively.

5. The electrical induction device according to claim 4 wherein said first shaped insulating means comprise a third and a fourth U-shaped bodies wrapping, at least partially, the upper and lower tip portions of the penultimate external turn, respectively.

6. The electrical induction device according to claim 5 wherein said first shaped insulating means comprise a fifth and sixth U-shaped bodies wrapping, at least partially, the upper and lower tip portions of the ante-penultimate external turn, respectively.

7. The electrical induction device according to claim 1 wherein said electrically insulating means comprise second shaped insulating means which are operatively coupled to and arranged around a portion of at least one electrical conducting element which is connected to and protrudes from said at least one inner winding.

8. An electrical induction device for high voltage applications, comprising:

a magnetic core having at least one leg and operatively coupled to a supporting structure;

at least one inner winding which is arranged around said leg and has a first rated voltage;

at least one outer winding which is arranged around said at least one inner winding and has a second rated voltage; and

electrically insulating means;

wherein said at least one inner winding comprises a plurality of substantially concentric turns formed by a sheet of electrically conducting material which is spirally wound, and wherein said electrically insulating means comprise at least one layer of electrically insulating material which is arranged between mutually facing surfaces of said concentric turns, and first shaped insulating means which edge, at least partially, at least one of the upper and lower external rims of said at least one inner winding;

wherein said electrically insulating means comprise second shaped insulating means which are operatively coupled to and arranged around a portion of at least one electrical conducting element which is connected to and protrudes from said at least one inner winding; and

wherein said second shaped insulating means comprise a first contoured body having a first L-shaped portion which is coupled to said at least one inner winding with a first side positioned substantially parallel to said leg and a second side positioned substantially perpendicular to said leg, and a second U-shaped portion rising from said second side of the L-shaped portion, which surrounds, at least partially, the portion of the conducting element which is connected to the inner winding.

9. The electrical induction device according to claim 8 , wherein said second shaped insulating means comprise a second contoured body which is positioned at the upper portion of said at least one inner winding so as to cover a region thereof.

10. The electrical induction device according to claim 9 , wherein said second contoured body has an angular sector configuration with an L-shaped side cross-section and is positioned at the upper portion of said at least one inner winding with a first side which is arranged substantially parallel to said leg and covers a portion of the outer surface of the last external turn, and a second side which is positioned substantially perpendicular to said leg and extends up to the most internal turn.

11. The electrical induction device according to claim 7 wherein said supporting structure comprises a plurality of tie rods, and said electrically insulating means comprise third shaped insulating means which are arranged around at least a portion of at least one tie-rod.

12. An electrical induction device for high voltage applications, comprising:

a magnetic core having at least one leg and operatively coupled to a supporting structure;

at least one inner winding which is arranged around said leg and has a first rated voltage;

at least one outer winding which is arranged around said at least one inner winding and has a second rated voltage; and

electrically insulating means;

wherein said at least one inner winding comprises a plurality of substantially, concentric turns formed by a sheet of electrically conducting material which is spirally wound, and wherein said electrically insulating means comprise at least one layer of electrically insulating material which is arranged between mutually facing surfaces of said concentric turns, and first shaped insulating means which edge, at least partially, at least one of the upper and lower external rims of said at least one inner winding;

wherein said electrically insulating means comprise second shaped insulating means which are operatively coupled to and arranged around a portion of at least one electrical conducting element which is connected to and protrudes from said at least one inner winding;

wherein said supporting structure comprises a plurality of tie rods, and said electrically insulating means comprise third shaped insulating means which are arranged around at least a portion of at least one tie-rod; and

wherein said third shaped insulating means comprise a first and a second layers of cellulose-based material which are tubularly wound around said tie-rod spaced apart from each other, and a third element made of insulating material which is arranged therebetween.

13. The electrical induction device according to claim 12 , wherein said first layer comprises a sheet of crepe-paper having a thickness ranging between 0.8 and 1.2 mm which is placed around said tie-rod, said second layer comprise a sheet of crepe-paper having a thickness ranging between 1 and 3 mm which is placed spaced from said first layer so as to define a channel there between, and said third element comprises a contoured body which is positioned inside said channel and mutually spaces out said first and second layers.

14. The electrical induction device according to claim 1 wherein said layer of electrically insulating material comprises two sheets of cellulose-based material mutually attached to each other.

15. The electrical induction device according to claim 1 , wherein the first shaped insulating means edge, at least partially, at least one of the upper and lower external rims of said at least one inner winding by covering at least a portion of at least one of the upper and lower external rims that is parallel to the leg and a portion of at least one of the upper and lower external rims that is perpendicular to the leg.