Application of Z-source Inverter in Distributed Generation Systems for Reduction of Harmonic and Unbalance of Network Current

The converters that employed in Distributed Generation (DG) systems do not utilize their complete capacity forever. The left capacity of the converters could be employed to contribute some auxiliary functions similar to reduction of harmonic and unbalance of the power distribution system. This paper proposes a DG system based on z-source inverter which designed to reduce harmonic and unbalance of the power distribution system. The DG system would inject the suitable amount of power into the network, and the controllers are designed to reduce the harmonics in the injecting current according to IEEE 1547. If the inverter does not work in its complete capacity, the left capacity is employed to decrease the total harmonic distortion (THD) and reduce unbalance of the network current. Simulation results demonstrate the reduction of THD and unbalance of line current to the acceptable limit set by IEEE standards.