Transformer protection system

Patent metadata

Field	Value
Publication number	US-9935454-B2
Application number	US-201514733568-A
Country	US
Kind code	B2
Filing date	Jun 8, 2015
Priority date	Dec 12, 2012
Publication date	Apr 3, 2018
Grant date	Apr 3, 2018

Abstract

An exemplary transformer protection system including a protective housing having a transformer which is arranged in the protective housing, a transformer core, and at least one primary-side electrical winding and a secondary-side electrical winding which is magnetically coupled to the primary-side electrical winding. The protection system also includes at least one detection apparatus for a measurement variable from which the occurrence of an interference arc within the protective housing can be derived, and an evaluation unit for generating a fault signal from the measurement variable of the at least one detection apparatus in the case of an interference arc. Further, the protection system includes at least one rapid-earthing apparatus for at least one of the electrical windings which is intended to be activated by the fault signal, wherein the rapid-earthing apparatus is designed in such a way that effective electrical earthing immediately after activation of the fault signal is ensured.

First claim

What is claimed is:

1. A dry transformer protection system comprising:
a protective housing;
a dry transformer arranged in said protective housing, said dry transformer having a transformer core and having at least one primary-side winding and a secondary-side electrical winding that is magnetically coupled to said primary-side winding;
at least one detection device for a measuring variable to determine whether an arc fault has occurred within the protective housing;
an evaluation unit for generating a fault signal from the measuring variable of the at least one detection device in the event of an arc fault; and
at least one high speed grounding device for at least the primary-side winding, the at least one high speed grounding device is configured to be activated by the fault signal,
wherein the high speed grounding device is configured such that an effective electrical grounding is ensured immediately after the fault signal is activated.

2. The dry transformer protection system as claimed in claim 1 , wherein the at least one detection device includes a light sensor for detecting flashes of light that occur within the protective housing.

3. The dry transformer protection system as claimed in claim 1 , wherein the protective housing includes multiple sub-divided inner regions, wherein each of these regions is allocated at least one light sensor.

4. The dry transformer protection system as claimed in claim 3 , wherein a common light sensor for at least two regions, said common light sensor having a light waveguide that protrudes into said regions or is guided through said regions.

5. The dry transformer protection system as claimed in claim 4 , wherein the light waveguide is provided for receiving light at least on part of a radial outer surface of the light waveguide.

6. The dry transformer protection system as claimed in claim 1 , wherein at least one detection device includes a current sensor for determining electric current that is flowing through at least one of the windings.

7. The dry transformer protection system as claimed in claim 1 , wherein the evaluation unit is configured such that a fault signal is only output in the case of an arc fault being detected respectively with reference to multiple physically independent measuring variables.

8. The dry transformer protection system as claimed in claim 1 , wherein the at least one high speed grounding device includes a drive that is based on a gas expansion that is initiated as an explosion.

9. The dry transformer protection system as claimed in claim 1 , wherein the protective housing is an arc fault housing.

10. The dry transformer protection system as claimed in claim 1 , wherein the at least one high speed grounding device is arranged outside the protective housing.

11. The dry transformer protection system as claimed in claim 1 , wherein the electrical windings are embodied in a three-phase manner.

12. The dry transformer protection system as claimed in claim 11 , wherein the high speed grounding device is provided for a single-phase activation.

13. The dry transformer protection system as claimed in claim 11 , wherein the high speed grounding device is provided for a three-phase activation between the respective phases.

14. The dry transformer protection system as claimed in claim 1 , wherein the at least one detection device includes a pressure sensor for detecting an increase in pressure within the protective housing.

15. The dry transformer protection system as claimed in claim 2 , wherein the at least one detection device further includes a pressure sensor for detecting an increase in pressure within the protective housing.

Assignees

• Abb Technology Ag
• Abb Schweiz Ag

Inventors

• Tepper Jens
• Tamzarti Abdelbahi
• Leenen Nils
• Staudinger Stefan

Classifications

• H02H1/0023

  sensing non electrical parameters, e.g. by optical, pneumatic, thermal or sonic sensors · CPC title

• H02H3/0935

  the timing being determined by numerical means · CPC title

• H01F27/402 Primary

  Association of measuring or protective means · CPC title

• H02H7/042

  for current transformers · CPC title

• H02H7/04 Primary

  for transformers · CPC title