Double-closed-loop control method and system for single-phase LC type grid-connected inverter

The invention belongs to the technical field of power inverter control, and discloses a double-closed-loop control method and system for a single-phase LC type grid-connected inverter. The method comprises the following steps: s101, solving a difference between a direct current side voltage reference value Vd* and an actual value Vd, and obtaining a secondary side filtering inductive current amplitude according to a voltage difference value; s102, taking a power grid voltage signal Vs, and obtaining a standard unit sinusoidal signal sin omega t through a phase-locked loop PLL; s103, multiplying the secondary side filter inductive current amplitude signal by the unit sinusoidal signal to obtain an inductive current standard reference value, subtracting the inductive current standard reference value from an inductive current actual value IL, and obtaining a modulation signal according to the inductive current difference value; s104, inputting the modulation signal into an SPWM module to obtain four driving sign