Peak Current Control for Three-Phase Inverter with LCL Filter

Numerous research studies have been conducted for the control of grid-tied converters during low voltage ride through (LVRT). Yet, transient behavior of the converter at the beginning of the grid voltage sag has rarely been studied. When a conventional linear control followed by a modulator is used, if the controller is not fast enough, the converter may suffer from high current spikes at the beginning of the fault. This abnormal current can saturate the inductors and damage the semiconductors permanently. In order to effectively limit the current spike, the peak current control (PCC) for three-phase grid-tied converter with an LCL filter has been developed.