On the effects of interharmonic distortion on grid connected three-phase PV inverters

The effects of interharmonic distortion on Photo Voltaic (PV) inverters whose control is based on the use of PLL systems are analyzed. After some brief recalls on typical PV inverter connection schemes and control strategies, the design of the PLL and its sensitivity to the presence of interharmonic distortion is analyzed. Finally, a case-study on a very simple system is discussed with reference to the Light Flicker phenomenon.