In the process of photovoltaic power generation

the power quality is not good. The reason is that the output current generally contains low-order harmonics

among which the low-order harmonics of 5 times and 7 times are most serious

due to the switching characteristics of the inverter. In order to suppress the low-order harmonics in the output current and reduce the loss of loads and line

a harmonic suppression control strategy based on grid-connected inverter topology of L-type is proposed in this paper. A harmonic modulation scheme based on SPWM harmonic injection

which is to inject compensation voltage of low-order harmonics of 5 th times and 7 th times

is discussed in detail. The purpose is reducing the specific harmonics of the output current and improving the power quality of the grid connection. The MATLAB/Simulink simulation and experiment verifies that this scheme can effectively reduce the specific sub-harmonic content in grid-connected current

reduce the harmonic distortion rate and improve the grid-connected power quality of photovoltaic power generation.