Influence of skin- and proximity effects on LV fuse gear

Abstract

ABB in Skien produces compact transformer stations for the distribution grid. Depending on the application, these can come with a significant number of different configurations. Manufacturers must prove that every unit satisfies the temperature limits given in the standards. Both the skin- and the proximity effect increase the resistance of AC circuits which increases power losses and can add undesirable heating.

This thesis aims to look at how the skin- and proximity effects influence LV fuse gear, and contains basic theory, COMSOL simulations focused the skin- and proximity effects, laboratory experiments and hand calculations.

The final results of the COMSOL simulations indicate that the losses increase as the distance between busbars decrease and that the losses are highest in the center busbar. The results also show that the losses do not increase linearly as the distance decreases.