Analisis Hubungan Daya Reaktif terhadap Variasi Pembebanan pada Generator Unit 4 PLTU PT Bintan Alumina Indonesia Berdasarkan Data Operasional SCADA

Abstract

Generators play a vital role in maintaining power system stability, particularly in regulating reactive power and power factor under varying load conditions. Variations in electrical load can affect the balance of active and reactive power generated by a generator. This study aims to analyze the relationship between reactive power and load variations in Generator Unit 4 at the PT Bintan Alumina Indonesia Coal-Fired Power Plant (PLTU) based on operational data obtained from the Supervisory Control and Data Acquisition (SCADA) system. A quantitative research method was employed by analyzing 30 days of generator operational data recorded at 1-hour intervals. The analyzed parameters included active power (P), reactive power (Q), voltage (V), current (I), frequency (f), power factor (PF), and excitation current. The data were processed through electrical parameter calculations and visualized using scatter plots to examine the relationships among the variables. The results indicate that excitation current has the strongest correlation with the reactive power of Generator Unit 4, with a correlation coefficient of r = 0,9062 and a coefficient of determination of R² = 0,8212. Excitation current regulates the magnitude of reactive power, which is subsequently associated with changes in power factor and voltage drop (ΔV). Furthermore, the relationship between active power and reactive power is positive but weak (r = 0,3593; R² = 0,1291), indicating that variations in reactive power are influenced more strongly by excitation current regulation than by changes in generator loading.