US 12,488,928 B2
Method for drying a transformer having a multistage cooling system, and cooling device controller for such a transformer
Mario Scala, Graz (AT)
Assigned to Siemens Energy Global GmbH & Co. KG, Munich (DE)
Appl. No. 17/604,502
Filed by Siemens Energy Global GmbH & Co. KG, Munich (DE)
PCT Filed Mar. 31, 2020, PCT No. PCT/EP2020/059101
§ 371(c)(1), (2) Date Oct. 18, 2021,
PCT Pub. No. WO2020/212133, PCT Pub. Date Oct. 22, 2020.
Claims priority of application No. 19170055 (EP), filed on Apr. 18, 2019.
Prior Publication US 2022/0208432 A1, Jun. 30, 2022
Int. Cl. H01F 7/06 (2006.01); H01F 27/02 (2006.01); H01F 27/14 (2006.01); H01F 27/32 (2006.01)
CPC H01F 27/14 (2013.01) [H01F 27/025 (2013.01); H01F 27/32 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A method for drying a transformer with a multistage cooling system,
the transformer having at least one transformer winding and at least one insulator for an electrical insulation;
the cooling system having cooling stages with a lowest cooling stage and a highest cooling stage, wherein said cooling stages are respectively associated with one loading state range of the transformer and are activated when a respective loading state range of the transformer is reached, and wherein the loading state range is a function that depends at least on a temperature of the transformer;
the method for drying the transformer, to be carried out during an operation of the transformer, comprising:
while the transformer is operating in the loading state range that is associated with a given upper cooling stage which lies above the lowest cooling stage, deactivating, or maintaining in a deactivated state, the given upper cooling stage, and activating, or maintaining in an activated state, a cooling stage which lies directly below the given upper cooling stage.