The utility model discloses an LCL type multi-photovoltaic compatible grid-connected
inverter which comprises a photovoltaic array, a DC / DC module, a
DC bus, a DC / AC inversion module, an
LCL filter and a
power grid which are connected in sequence, the DC / AC inversion module is sequentially connected with a PWM generator and an
adder, two paths of input of the
adder are connected with a first multiplier and a second multiplier respectively, and the first multiplier and the second multiplier are connected with a
power grid. Two paths of input of the first multiplier are respectively connected with a PI controller and a first analog-to-
digital converter, and two paths of input of the second multiplier are respectively connected with an RC repetitive controller and a second analog-to-
digital converter; the first comparison circuit generates a first output level according to the current
error signal, and the second comparison circuit generates a second output level according to the
harmonic signal. According to the utility model, a pure hardware circuit is constructed to realize weight switching, the fusion proportion of the PI controller and the RC repetitive controller can be switched according to the working condition of the
system, the output of the
inverter is adjusted according to the reference and the
electric energy quality requirement, and the use effect is good.