Analysis of unbalanced load effect of three phase transformer feedback 61-103 performance on the various connection windings

Transformer is an electrical equipment which transfers electrical power from one circuit to another circuit through magnetic fields. In the ship electrical system, unbalanced load on the three-phase of transformer is often found. It is due to the load operational time which does not occur simultaneously. If the unbalanced load occurs continuously on the transformer, it will decrease the transformer's performance. This research aims to test the three-phase transformer feedback 61-103 on the various connection winding in marine electrical and automation laboratory system. It was conducted by collecting the data to get the results of efficiency, voltage regulation, and unbalanced load calculation to find out the effect of unbalanced load to the performance of each transformer winding. From the results of the test, the highest efficiency was 93.8% in the wye-Zigzag wye connection winding and delta-connected load. The lowest voltage regulation was 0.9% in the wye-delta connection winding and wye-connected load and delta-connected load. The lowest unbalanced load was 5.0% in the delta-delta connection winding and wye-connected load.