Power quality assessment in 3-Ф grid connected PV system with single and dual stage circuits

• Comparative assessment for single and dual stage grid connected PV system.
• Z source Inverter based on SVPWM control technique.
• Inclusion of hybrid filter for power quality improvement.
• Stability analysis of single and dual stage circuit configuration.
• Experimental analysis to valid the superiority of single stage configuration.

This paper addresses the assessment of power quality (PQ) in 3-Ф grid connected photovoltaic (PV) system that consists of single and dual stage power extraction circuits. The single stage circuit comprises of Z-source inverter (ZSI) controlled by space vector pulse width modulation (SVPWM), while dual stage is traditional boost based voltage source inverter controlled by sinusoidal pulse width modulation. The PQ of signals in both the circuits is analyzed during transient variations like solar intensity and load conditions, with/without use of hybrid filter. The simulation and experimental results suggest an improved smooth sinusoidal waveform available at PCC in case of ZSI based circuit using hybrid filter, if power quality improvement is of prime importance with both linear and nonlinear load connected in the system.