Radiator for a transformer having improved cooling

1. Radiator for a transformer, the radiator comprising a plurality of radiator panels with at least a first radiator panel and a second radiator panel, the first and the second radiator panels extending in a substantially vertical direction, and each of the plurality of radiator panels having a bottom edge,

the first and the second radiator panels forming an air duct providing a gap there-between having a width of smaller than 90 mm, and

the bottom edge of the first radiator panel being located at a lower vertical height position than the bottom edge of the second radiator panel;

the first radiator panel being located at a side of the radiator that is adapted to be attached to a transformer in such a manner that the first radiator panel and a side of the transformer form a transformer air duct; and

each radiator panel of the plurality of radiator panels having a horizontal depth of at least 8 times the width of the air duct.

2. The radiator of claim 1 , wherein, when the radiator is attached to the transformer, the first radiator panel and a side of the transformer form a transformer air duct.

3. The radiator of claim 1 , wherein the radiator panel bottom edges of at least three consecutive radiator panels form a line that is in average monotonically ascending with respect to a horizontal in a direction from the first radiator panel to the second radiator panel, the at least three consecutive radiator panels comprising the first and the second radiator panels.

4. The radiator of claim 3 , wherein the radiator panel bottom edges of the at least three consecutive radiator panels form a straight line that is monotonically ascending with respect to the horizontal in a direction from the first radiator panel to the second radiator panel.

5. The radiator of claim 1 , wherein the vertical height position of the radiator panel bottom edges increases monotonically with respect to a horizontal in a direction from the first radiator panel to the second radiator panel.

6. The radiator of claim 1 , wherein the radiator panel top edges are located at substantially a same vertical height position.

7. The radiator of claim 1 , wherein the radiator bottom edges form an inclined angle relative to a horizontal that is at least 10°, or wherein the radiator panel bottom edges form a line that is substantially inclined at an angle of at least 10° to the horizontal in a direction from the first radiator panel to the second radiator panel.

8. The radiator of claim 1 , wherein the radiator panels of the radiator are substantially formed as plate-like structures that extend in a vertical direction.

9. The radiator of claim 1 , wherein a chimney is arranged on top of at least some of the radiator panels.

10. The radiator of claim 1 , wherein a chimney is arranged on top of at least some of the radiator panels, comprising an outermost radiator panel wherein the outermost radiator panel is the radiator panel with a greatest distance to the first radiator panel.

11. The radiator of claim 1 , wherein a chimney is arranged on top of at least 50% of the radiator panels.

12. The radiator of claim 1 , wherein the radiator is for an oil-filled transformer, and wherein the radiator comprises an oil supply duct for supplying oil to be cooled from the transformer to the radiator, and an oil return duct for returning cooled oil from the radiator to the transformer.

13. Transformer comprising at least one radiator comprising a plurality of radiator panels with at least a first radiator panel and a second radiator panel, the first and the second radiator panels extending in a substantially vertical direction, and each of the plurality of radiator panels having a bottom edge,

the first and the second radiator panels forming an air duct providing a gap there-between having a width of smaller than 90 mm, and

the bottom edge of the first radiator panel being located at a lower vertical height position than the bottom edge of the second radiator panel;

the first radiator panel being located at a side of the radiator that is adapted to be attached to a transformer in such a manner that the first radiator panel and a side of the transformer form a transformer air duct;

and

each radiator panel of the plurality of radiator panels having a horizontal depth of at least 8 times the width of the air duct.

14. The transformer claim 13 , wherein a height of the radiator panel that is located closest to a side wall of the transformer is substantially equal to a height of the transformer and wherein the radiator panel top edges are located at substantially a same vertical height position.

15. The transformer of claim 13 , wherein a height of the radiator panel that is located closest to a side wall of the transformer is substantially equal to a height of the transformer.

16. The transformer of claim 13 , wherein, when the radiator is attached to the transformer, the first radiator panel and a side of the transformer form a transformer air duct.

17. The transformer of claim 13 , wherein the radiator panel bottom edges of at least three consecutive radiator panels form a line that is in average monotonically ascending with respect to a horizontal in a direction from the first radiator panel to the second radiator panel, the at least three consecutive radiator panels comprising the first and the second radiator panels.

18. The transformer of claim 17 , wherein the radiator panel bottom edges of the at least three consecutive radiator panels form a straight line that is monotonically ascending with respect to the horizontal in a direction from the first radiator panel to the second radiator panel.

19. The transformer of claim 13 , wherein the vertical height position of the radiator panel bottom edges increases monotonically with respect to a horizontal in a direction from the first radiator panel to the second radiator panel.

20. The transformer of claim 13 , wherein the radiator panel top edges are located at substantially a same vertical height position.