When the original photovoltaic system is upgraded to family photovoltaic energy storage system

the single-phase photovoltaic inverter should meet the need of continued grid-connected operation under energy storage battery input condition. Firstly

equivalent circuit of photovoltaic array and Li-ion battery pack are constructed and studied. Based on these math models

comparison of the impacts brought about by two different input conditions is made. Under energy storage battery input condition

for the inherent AC/DC coupling problem in single-phase inverter

there is more serious contamination of the second harmonic current. Then

the equivalent impedance of ripple current based on Boost DC/DC convertor small signal mode is studied. A novel active input ripple current mitigating technique based on double channel current feedback is proposed. The control system using extraction method of ripple component and trap inhibition for ripple voltage in DC-link

based on the third-order general integrator

is analyzed and simulated with MATLAB. Finally

experimental results using a 5 kW prototype have validated the proposed control strategy. This work is supported by National High Technology Research and Development Program of China(863 Program)(No. 2012AA051601)and National Natural Science Foundation of China(No. 61364007).