In the simulation circuit as the figure 8, to join the PI control in inverter feedback control.
Inverter current compared with a given current value,
the error after the PI controller generates PWM signals that it can control on and off to the 1228 main circuit,
thus to control the inverter circuit.
The grid voltage waveform and inverter voltage waveform and the grid current are shown in figure 9 and figure 10 and figure 11.