Bibliothèque de vidéos techniques
Inside a Large Transformer Core: Cooling Ducts and Heat Paths
Présentation technique
Heat travels differently along a steel sheet and across a coated stack. This video compares equal-length circular core limbs: at the same loss per unit volume, doubling the diameter gives four times the heat generation and twice the side surface area. It connects this geometry to cooling ducts, open flow paths, spacer pressure and net steel section.
Transcription
A cool surface can hide a hotter core centre. Heat moves more easily along each sheet than across the coated stack. A larger limb makes the escape path longer. Compare equal lengths of circular limbs, with the same loss per unit volume. Double the diameter: heat generation becomes four times greater, but the side surface only doubles. Cooling ducts split the stack into thinner packets, bringing oil closer to the interior. Spacers must keep those ducts open after clamping, without concentrating pressure. Each duct also removes space available for steel. Duct positions, flow paths and net steel section must therefore be designed together. A surface reading alone cannot establish the centre temperature.