Grid current and voltage waveforms are shown in fig. 14. From this Fig Grid current and voltage waveforms
are positive. So, the power at the input side of the inverter is positive. Hence we say that act as a source. When the grid
voltage and inverter current both of them in-phase and it provides power factor is nearly unity. The current flows from
the grid to inverter. Hence we absorb a power from the utility grid. So, our inverter acts as a load.