Single phase inverter-current control loop

hisham.i

Hello

I am designing single phase inverter with TMS320LF2406 DSP.

I created sinusoidal output voltage, and now i want to make regulation.

While reading about regulation i found that it is recommended to use outer loop as voltage loop to generate Iref using PI controller, then this Iref is entered to inner loop ( current loop) where its output is entered to another PI controller to generate the PWM duty cycle.

What is the advantage of using the inner current loop? why we cannot only use the voltage control loop to determine the duty cycle?

Regards,

Hisham Issa