On the effect of asymmetry and non-sinusoidal currents on the loss of electricity in a power transformer

Using a full-factor active experiment on a physical model, a regression equation for calculating power losses in a power transformer has been obtained. During the experiments, the corrected electric power losses in the transformer magnetic core and windings from the main frequency current have been subtracted from the total electric power losses. On the basis of the obtained mathematical model it is proposed to calculate electric power losses in a power transformer according to the known values of transformer K-factor and the ratio of zero sequence current of the basic harmonic to the current of the 3rd harmonic in the zero conductor. The recommended range of applicability of the mathematical model by K-factor is from 1.04 to 1.10, by the ratio of zero sequence current of the main harmonic to the 3rd harmonic current from 0.68 to 6.82.