Experimental Works to Improve Power Quality of the Existing PV Solar Inverters


  • Ali Algaddafi Electrical and Electronics Department, University of Sirte, Sirte – Libya.
  • Abdelrahim N. Esgiar Electrical and Electronics Department, University of Sirte, Sirte – Libya.
  • Eljaroshi Diryak Electrical and Electronics Department, University of Sirte, Sirte – Libya.
  • I.M. Saleh Engineering Mechanics of Aeronautics, Power and Production Department, University of Sirte, Sirte – Libya.




PV Array Emulator, Analogue Computation Circuit (ACC), PV inverter, AC Mini-Grid, Power Quality (PQ)


Solar energy development has attracted significant research attention, due to it offering many advantages that include being a safe, clean, and non-finite resource with no operational costs or moving parts. Therefore, solar systems are expected to play a significant role in the future of electricity supply, but, the power electronics used to connect these resources to the grid may face problems. This paper presents improving the power quality of the existing PV inverter by integrating it with a bidirectional inverter along with a battery storage system. A 6 kWh AC Mini-Grid is developed and tested with a PV inverter. The experimental works found that the PV inverter has high the Total Harmonic Distortion (THD) of the output current that may reach up to 24%, while when this PV inverter was connected to the proposed system, the THD of the output current of the PV inverter was reduced to 0.64 %. The response of the battery storage is very smooth and fast, providing a stable and reliable output power in both cases when a domestic load is supplied from the solar system or the battery storage.


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