IMPACT OF ELECTROMAGNETIC SHIELDS ON LOCAL OVERHEATING IN TRANSFORMER TANK

The paper describes different influences of magnetic and electromagnetic shielding on stray flux distribution in power transformers. application shields the reduction high temperature spots transformer tank is studied detail by using a 3D model for coupled electromagnetic-thermal calculation. analysis models with various shapes dimensions show which factors are most important hot tank. Proposed solution should reduce total loss maximum value. It shown that these values not always achieved area endangered from current leads. choice shield must take into account surrounding component material properties lead arrangement.