Cooling arrangement and method for cooling at least one oil-to-air external heat exchanger

Method performed by a cooling arrangement for cooling at least one oil-to-air external heat exchanger, OAEHE, in a transformer, the cooling arrangement comprising at least one impeller-motor device, at least one fluid pipe and at least one fluid discharge device comprising a fluid inlet for receiving a humidity-controlled fluid from the at least one fluid pip, and at least one fluid outlet, the method comprising:

• supplying the humidity-controlled fluid into the at least one fluid pipe, using the at least one impeller-motor device;
• transporting the humidity-controlled fluid along the at least one fluid pipe to the inlet of the at least one fluid discharge device;
• causing the humidity-controlled fluid to flow through the at least one fluid discharge device;
• and
• discharging the humidity-controlled fluid through the at least one fluid outlet in a direction of the at least one OAEHE.

A transformer comprising:

• an oil-to-air external heat exchanger, OAEHE;
• and
• a cooling arrangement comprising:
• at least one impeller-motor device, at least one fluid pipe;
• and
• at least one fluid discharge device, the at least one fluid discharge device comprising a fluid inlet for receiving a humidity-controlled fluid from the at least one fluid pipe, and at least one fluid outlet arranged to direct the humidity-controlled fluid towards the OAEHE, the at least one impeller-motor device being adapted to supply the humidity-controlled fluid to the inlet of the at least one fluid discharge device via the at least one fluid pipe and cause the humidity-controlled fluid to flow through the at least one fluid outlet of the at least one fluid discharge device in a direction of the at least one OAEHE.