Multielectrode power capacitor with reduce noise vibration

• US 10,658,119 B1
• Filed: 04/25/2018
• Issued: 05/19/2020
• Est. Priority Date: 04/26/2017
• Status: Active Grant

• Current Assignee: Hitachi Energy Limited
• Original Assignee: ABB Schweiz AG (ABB Limited)
• Inventors: Bandalo, Felix
• Primary Examiner(s): Thomas, Eric W
• Application Number:
  US16/606,511
• Publication Number:
  US 20200135405A1
• Time in Patent Office: 755 Days
• CPC Class Codes: H01G 4/008 Selection of materials
• CPC Class Codes: H01G 4/224 Housing; Encapsulation
• CPC Class Codes: H01G 4/232 electrically connecting two or more layers of a stacked or rolled capacitor
• CPC Class Codes: H01G 4/32 Wound capacitors
• CPC Class Codes: H01G 4/38 Multiple capacitors, i.e. structural combinations of fixed capacitors

Abstract

A power capacitor including: a casing, a first bushing, a second bushing or an earthing stud having the same electric potential as the casing, wherein the first and second bushing extend through the casing, a dielectric liquid, and a plurality of wound capacitor elements, each wound capacitor element including: a first electrode having two first layers of electrically conducting material connected to the first bushing, the two first layers being arranged movable towards and from each other, a second electrode having two second layers of electrically conducting material connected to the second bushing or to the earthing stud, the two second layers being arranged movable towards and from each other, and a dielectric layer arranged between the first electrode and the second electrode, wherein the two first layers, the two second layers and the dielectric layer are together wound in a plurality of turns to obtain a plurality of layers of the first electrode, of the second electrode and of the dielectric layer, wherein the wound capacitor elements are arranged in a stacked manner in the casing, adjacent wound capacitor elements being in direct contact with each other, and wherein the capacitor elements are submerged in the dielectric liquid.

Claims

1. A power capacitor comprising:

a casing,

a first bushing,

a second bushing or an earthing stud having the same electric potential as the casing,

wherein the first bushing and the second bushing extend through the casing,

a dielectric liquid, and

a plurality of wound capacitor elements, each wound capacitor element including;

a first electrode having two first layers of electrically conducting material connected to the first bushing, the two first layers being arranged movable towards and from each other,

a second electrode having two second layers of electrically conducting material connected to the second bushing or to the earthing stud, the two second layers being arranged movable towards and from each other, and

a dielectric layer arranged between the first electrode and the second electrode,

wherein the two first layers, the two second layers and the dielectric layer are together wound in a plurality of turns to obtain a plurality of layers of the first electrode of the second electrodes and of the dielectric layer,

wherein the wound capacitor elements are arranged in a stacked manner in the casing, adjacent wound capacitor elements being in direct contact with each other, wherein the capacitor elements are submerged in the dielectric liquid.

2. The power capacitor as claimed in claim 1, wherein the two first layers have the same layer thickness.

3. The power capacitor as claimed in claim 1, wherein the two second layers have the same layer thickness.

4. The power capacitor as claimed in claim 3, wherein each of the two second layers is a metallization layer provided on a respective side of a film.

5. The power capacitor as claimed in claim 1, wherein each of the two first layers is a conducting foil.

6. The power capacitor as claimed in claim 1, wherein each of the two first layers is a metallization layer provided on a respective side of a film.

7. The power capacitor as claimed in claim 1, wherein each of the two second layers is a conducting foil.

8. The power capacitor as claimed in claim 1, wherein each of the two second layers is a metallization layer provided on a respective side of a film.

9. The power capacitor as claimed in claim 1, wherein the first electrode includes exactly two first layers of electrically conducting material.

10. The power capacitor as claimed in claim 1, wherein the second electrode includes exactly two second layers of electrically conducting material.

11. The power capacitor as claimed in claim 1, wherein the capacitor elements are flattened.

12. The power capacitor as claimed in claim 1, wherein for each capacitor element each of the two first layers consists of a respective single first continuous layer and each of the two second layers consists of a respective single second continuous layer.

13. The power capacitor as claimed in claim 12, wherein each of the first two layers and each of the second two layers extend along a majority of the axial length of the capacitor element.

14. The power capacitor as claimed in claim 13, wherein each of the first two layers extends from a first axial end of the capacitor element towards an opposite second axial end of the capacitor element terminating before reaching the second axial end, and wherein each of the second two layers extends from the second axial end towards the first axial end terminating before reaching the first axial end.

15. The power capacitor as claimed in claim 1, wherein the dielectric layer is arranged between the first electrode and the second electrode, whereby the first electrode, the dielectric layer and the second electrode are arranged parallel to each other in a sandwiched configuration.

16. The power capacitor as claimed in claim 1, wherein when the first electrode has a positive or negative electric potential for each capacitor element a first layer of the first electrode is attracted to one layer of the second layers arranged on the opposite side of the dielectric layer, and another layer of the second layers of the second electrode, adjacently arranged to the one layer, and the one layer repel each other.

17. The power capacitor as claimed in claim 16, wherein when the first electrode has a positive or negative electric potential for each capacitor element the two first layers repel each other.