The invention discloses an active high-frequency damping method for current control for an LCL type grid-connected
inverter. The active high-frequency damping method specifically comprises the following steps that a current reference value i<L1_ref> on the
inverter side and feedback quantity, that is, a predicting current hat{i}<L1> are subjected to subtraction to obtain an error value
delta e, and the error value is output by a proportional controller; output signals are divided into three
signal flows, one of the
signal flows is used as input of a high-frequency damping unit, one of the
signal flows is output through a current reconstruction and preset unit part, another one of the signal flows and a common
coupling voltage v<pcc> which has a feed-forward coefficient k<g> are subjected to addition, and the sum is output through a time delaying unit; and an output value acts on a controlled object to obtain an output value, that is, an in-grid current i<L2>, the output of the currentreconstruction and preset unit part and the in-grid current i<L2> are subjected to addition, and the predicting current hat{i}<L1> is obtained. A current
reconstruction method avoids sampling of a current on the
inverter side, reduces the complexity of
system hardware, improves invariant features of a
system, compensates
delay of the
system, and reduces dynamic and static errors of the system.