Transformer with temperature-dependent cooling function

Patent metadata

Field	Value
Publication number	US-10629356-B2
Application number	US-201716071569-A
Country	US
Kind code	B2
Filing date	Jan 18, 2017
Priority date	Jan 20, 2016
Publication date	Apr 21, 2020
Grant date	Apr 21, 2020

Abstract

An electric device has a housing and an active part in the housing that can be supplied with a high voltage and that generates heat when operated. The housing is filled with an insulating liquid for cooling. A cooling system for cooling the insulating liquid has at least one cooling element which is connected to the external atmosphere in a heat-conductive manner and via which the insulating liquid is conducted. Temperature fluctuations of the electric device are limited or even prevented in an inexpensive manner. The cooling system has a rising section which is connected to the housing, is provided with rising branches, and is connected to a cooling element at each rising branch. The volume of the rising section is selected on the basis of a thermal expansion coefficient of the insulating liquid such that the fill state reaches a different number of rising branches at specific temperatures.

First claim

The invention claimed is:

1. An electrical device, comprising:
a housing;
an active part disposed in said housing, said active part being subject to high voltage and generating heat when operated;
an insulating liquid for cooling filled in said housing; and
a cooling system for cooling said insulating liquid,
said cooling system having a rising section connected to said housing for carrying said insulating liquid, said rising section being formed with a plurality of rising branches and having a respective cooling element connected at each said rising branch, said cooling elements being thermally conductively connected to an ambient atmosphere;
wherein a volume of said rising section is selected in dependence on a coefficient of thermal expansion of said insulating liquid such that a filling level reaches a different number of said rising branches at prespecified temperatures.

2. The electrical device according to claim 1 , wherein said rising section has at least one inclined section which runs in an inclined manner in relation to a side wall of said housing, and wherein said rising branches are arranged in said inclined section.

3. The electrical device according to claim 2 , wherein each said cooling element is a radiator which has a plurality of inner cooling channels.

4. The electrical device according to claim 2 , wherein each rising branch is connected to a separate cooling pipe.

5. The electrical device according to claim 1 , wherein said rising section has a vertical pipe section that extends said housing in a direction of a side that is averted from a base wall, and wherein said rising branches are arranged in said vertical pipe section.

6. The electrical device according to claim 5 , wherein said cooling element is a pipe cooling means having an output connected to a base region of said housing, and wherein each said rising branch is connected to an input of said tubular pipe cooling means.

7. The electrical device according to claim 6 , comprising a heat exchanger having an output connected to a base region of said housing, and wherein at least one rising branch is connected to an input of a pipeline which leads to said heat exchanger.

8. The electrical device according to claim 7 , wherein said rising branch of said pipeline which leads to the input of said heat exchanger is arranged beneath at least one further rising branch for a further said cooling element.

9. The electrical device according to claim 1 , wherein said housing, the cooling elements and said rising section form a pressure-resistant, hermetically sealed unit, and a space above the filling level of said insulating liquid is filled with a compressible inert gas.

10. The electrical device according to claim 1 , wherein said rising section is formed with an opening above a maximum filling level of said insulating liquid, wherein a gas exchange with a surrounding area or further vessels is possible through said opening in an event of changes in volume which are caused by changes in a temperature of said insulating liquid, and wherein an interior of said cooling elements entirely or partially absorbs the fluctuations in the volume of said insulating liquid.

11. The electrical device according to claim 1 , wherein a rising branch is connected to a heat pipe.

12. The electrical device according to claim 1 , further comprising a fan for intensifying a cooling effect of said cooling system.

13. The electrical device according to claim 12 , further comprising a filling level sensor, wherein said fan has a regulating device which is connected to said filling level sensor.

14. The electrical device according to claim 1 , wherein said cooling elements are arranged with a vertical offset from one another.

15. The electrical device according to claim 1 , wherein said electrical device is a transformer or an inductor coil.

Assignees

• Siemens Ag

Inventors

• Findeisen Joerg

Classifications

• H01F27/08

  Cooling (heat-transfer elements F28F); Ventilating (structural details of casings H01F27/02) · CPC title

• H01F27/14

  Expansion chambers; Oil conservators; Gas cushions; Arrangements for purifying, drying, or filling · CPC title

• H01F27/025 Primary

  Constructional details relating to cooling · CPC title

• F28F2250/104

  with parallel flow · CPC title

• H01F27/12 Primary

  Oil cooling · CPC title