In view of similar structure between the photovoltaic（PV）inverter and the active power filter（APF）

it is of great significance to develop the PV inverters with harmonic suppression functions. The accurate tracking and rapid response to the phase and amplitude of the harmonic components is the guarantee of the effective use of the PV inverter to suppress the harmonic. In this paper

a harmonic suppression control method of PV inverter based on improved PI and repetitive control is proposed. This method can make photovoltaic inverters use PI controller to output fundamental active power

and use repetitive controller to output high accuracy harmonic current compensation

and simultaneously with consideration of one cycle delay dynamic response of the repetitive controller. Finally

it is shown by the simulation result that the proposed control strategy

compared to the traditional harmonic suppression method

can achieve multiple harmonic suppression withless calculation

and can ensure the steady-state accuracy and dynamic response speed of the active output and harmonic suppression of the photovoltaic inverter.