In recent years

the issue of ultra-high harmonics due to wide application of power electronic devices has attracted attention

while

the study on the characteristics of ultra-high-harmonic emission of photovoltaic power generation is still insufficient. In this paper

its generated harmonic amplitude and distribution law are analyzed by the use of typical voltage source inverter using bipolar modulation as an example and such direct affecting factors generating ultra-high harmonics as switching frequency

modulation ratio and DC side voltage are defined. Then

the indirect influence of parameters of filter

controller

the control of MPPT and different power levels on the ultra-high harmonics is analyzed emphatically

and the basis for selecting LCL filterparameters is given.The main frequency distributionrange and overall content of ultra-high harmonics of photovoltaic power generation is quantitatively analyzed on the basis of the actually measured data of certain photovoltaic system. Finally

a simulation model of photovoltaic power generation system is set up based on Matlab/Simulink to verify the above analysis results.