Abstract
This paper presents a method for estimation of core losses in banks of
single phase power transformers that are subjected to an injected DC
current such as geomagnetically induced currents (GIC). The main procedure
of the core loss calculation is to obtain a magnetic flux density waveform
in both time and location by using a novel algorithm based on 3D FEM
inside the core and then to calculate the loss distribution based on loss
separation theory. Also, a simple and effective method is proposed for
estimation of losses of asymmetric minor loops by using combination of
symmetric loops. The effect of DC biasing on core losses in single phase
power transformers is investigated and the sensitivity of core type and
material is evaluated. the results shows that DC current biasing could
increase core losses up to 40 percent or even more.
Go to article