Perbaikan Arus Sekunder Regulator Tegangan Beban untuk Menaikkan Kapasitas Penyearah Silikon dengan Pemasangan Kapasitor Bank Studi Kasus : di PT Indonesia Asahan Aluminium (Persero)

Abstract

Supply of DC current for an aluminum smelting electrolysis process at PT Indonesia Asahan Aluminium (Persero) currently up to 193 kA only. Meanwhile the Load Voltage Regulator (LVR) Transformer on the upstream of silicon rectifier is still loaded of 90%. This was caused of the secondary current of LVR transformer 182 MVA has already reached its maximum rating of 3180 A. This condition is an affect of its low power factor about 0.88 (lagging). There is still an opportunity to optimize LVR power supply by improving its power factor through capacitor bank installation thus the potline DC current supply can be increased In this research work the capacitor bank capacity determination, load flow and harmonic distortion analysis have been discussed ETAP 120 software has been utilized for system modeling and power system analysis. The power factor improvement has been implemented by installing Capacitor Bank 90 MVAR at 33 kV Bus of LVR secondary side. The result show that power factor of LVR transformer was improved from 0.88 to more than 0.95 and the DC current also increased from 193 k4 to 219 kA. budividual harmonic distortions of odd order in potline were decreased and total harmonic distorsions generally were still fine according to IEEE 519-1992. The rise of DC current will be a valuable improvement that will escalate the aluminum production at plant