Analysis of Power Losses in 6.3 Kv Step Down Transformers at PT. Permata Group
Keywords:
Step-Down Transformer, Power Loss, Efficiency, Loading Factor, Load Optimization, Under-UtilizationAbstract
This study analyzes power losses in a 6.3 kV step-down transformer with a capacity of 4,000 kVA at PT Permata Group, which distributes energy from the medium voltage system to the low voltage system. The analysis is based on nameplate data and field measurements, covering core losses (P₀), copper losses (Pcu), efficiency, and the effect of harmonics. The results show an increase in copper losses from 32,000 W to 32,080 W and core losses from 4,500 W to 5,200 W. The THD current value of 5.0% is still in accordance with the IEEE 519-2014 standard (≤8%). Maximum efficiency was achieved at 80% load with an actual value of 99.13%, slightly lower than the nameplate value of 99.17%. The transformer's condition was found to be very good and can serve as a reference for predictive maintenance and industrial power quality evaluation.
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