An equivalent circuit model for star-star-delta_utilized distribution transformer

In the recent years there has been excessive use of nonlinear loads in power distribution network resulting in the injection of harmonics into the utility power system. The triplen harmonics due to non-linear loads circulate in the conventional delta-star distribution transformer resulting in excessive power losses. Star-star-delta_utilized transformer is a modified distribution transformer configuration suggested recently which helps in recovering and utilizing the power wasted due to circulating harmonics in the transformer delta winding. This is achieved by connecting a load across the zero potential terminals of the tertiary delta winding of the transformer. This paper presents a three phase equivalent circuit model for the star-star-delta_utilized transformer. The proposed dependent source model is simulated and compared with the performance of the available transformer model of MATLAB Simulink. The results show that at steady state the performance of the proposed model can replicate the performance of the Simulink model.