ANALISIS PENGARUH BEBAN HARMONISA TERHADAP DERATING KAPASITAS TRANSFORMATOR DISTRIBUSI PADA PENYULANG DUKU PT. PLN (PERSERO) ULP SENTANI DENGAN MENGGUNAKAN METODE THDF

Abstract

Technological advancements have driven changes in the characteristics of electrical loads due to the use of modern electronic devices such as inverters, rectifiers, and variable frequency drive motors. These loads are non-linear, leading to the distortion of sinusoidal waveforms and the generation of harmonics. This condition occurs at the Duku Feeder of PT. PLN (Persero) ULP Sentani, where the majority of the customers are households with high usage of electronic equipment. This study aims to analyze the impact of non-linear loads on the reduction of distribution transformer capacity using the Total Harmonic Derating Factor (THDF) method. The research was conducted through field observations at three distribution substations on the Duku Feeder, using an AC Clamp Power Meter Hioki CM3286-50 to measure harmonics from orders 1 to 30. The measurement results were compared with the IEEE 519-2014 standard and then analyzed using the THDF method. The results show that the Total Harmonic Distortion of current (THDi) at each distribution substation exceeded the IEEE 519-2014 standard. Transformer capacity experienced derating: STN 020 from 400 kVA to 365.6 kVA (a decrease of 8.6%), STN 308 from 200 kVA to 183.6 kVA (8.2%), and STN 186 from 160 kVA to 143.2 kVA (10.8%). These findings emphasize the need for continuous monitoring of load patterns to reduce harmonic pollution and maintain the reliability of distribution transformers.