A new approach of core structure model for 3-phase distribution transformer

摘要

Reducing the losses of 3-phase transformers is still considered a significant target by many transformer designers and manufacturers. Core joint design is one of the factors related to the losses. In previous studies, core losses and flux density distribution motivated researchers to design appropriate T-joints. However, the variation of load and thermal profiles are the most important factors related to the losses in transformers. This study proposed a new T-joint configuration for the core of the 3-phase transformer. The proposed model was built after considering the variation of load and thermal profiles. Results were compared with those of conventional T-joint designs, such as butt-lap and 45 degrees mitered designs, that are currently used. The no-load losses of the proposed model were reduced by more than 6.8% and 10% compared with those of the butt-lap and mitered T-joint designs, respectively. Furthermore, the total losses, the hot spot temperature of the core, and the oil temperature decreased significantly. The proposed model contributes to the literature on new T-joint designs for improving transformer performance.