Evaluating the Impact of Grid Impedance and Load Dynamics on Power Quality: A Comparative Study of Distıinct load Scenarios
III. International Conference on Engineering Sciences (ICES2026), Konya, Türkiye, 4 - 06 Eylül 2026, ss.588-596, (Tam Metin Bildiri)
- Yayın Türü: Bildiri / Tam Metin Bildiri
- Basıldığı Şehir: Konya
- Basıldığı Ülke: Türkiye
- Sayfa Sayıları: ss.588-596
- Bursa Uludağ Üniversitesi Adresli: Evet
Özet
Uncontrolled three-phase diode bridge rectifiers draw non-sinusoidal currents that can adversely affect power quality in industrial electrical systems. This study investigates the effects of DC-side load configuration and line impedance on grid-side current harmonics using MATLAB/Simulink. Three circuit configurations are evaluated through nine operating cases: a purely resistive load supplied by an ideal source, a resistive load with parallel capacitive filtering supplied by an ideal source, and the same RC load supplied through line resistance and inductance. The simulations use a balanced 230 V phase to- neutral RMS supply at 50 Hz, a 10 Ω load resistor, and a 500 μF capacitor where applicable. Current waveforms, fundamental and total RMS currents, harmonic spectra, and mean DC output voltage are evaluated over a common ten-cycle interval, with current total harmonic distortion (THD) calculated through the 50th harmonic. Adding the capacitor increases THD from 30.76% to 56.62%, while introducing a line resistance of 0.86 Ω per phase without inductance reduces it to 35.54%. At this fixed resistance, the response to increasing line inductance is non-monotonic: THD initially rises to 37.32% at 0.5 mH before decreasing to 8.79% at 10 mH. Spectral analysis indicates that individual harmonic components do not necessarily follow the overall distortion trend. Across the inductance sweep, the mean DC output voltage decreases from 459.40 to 383.80 V, demonstrating that reduced distortion is accompanied by a change in operating point. The results highlight the need to consider line resistance and inductance separately and to assess harmonic distortion alongside line losses and DC output requirements. The investigated impedance values provide a controlled sensitivity analysis rather than a validated representation of a particular utility feeder.