Photovoltaic array based multilevel inverter for power conditioning

This paper proposes a photovoltaic (PV) array supported five-level cascaded H-bridge multilevel inverter (CHBMLI) based shunt active power filter (SAPF). The combined system is used for power conditioning application to improve power quality in the distribution network. The photovoltaic supported CHBMLI makes attractive solution because this inverter need isolated dc source in the dc side of the each H-bridge. The SAPF is used to compensate both reactive and harmonic components of the current drawn by the non linear load. Additionally, it also balances the supply current for unbalanced load. In this paper it is shown that the PV based multilevel inverter configured SAPF not only compensates the harmonic current, reactive power and unbalancing but also injects real power whenever it is demanded in the distribution system. The compensation and power flow control in this paper is developed based on the instantaneous power theory. The simulation results presented in this paper evidently proves the compensation capabilities and real power injection. The simulation studies are carried out under power system computer aided design PSCAD/EMTDC 4.2 environment.