Cost-effective deadbeat current control for wind-energy inverter application with LCL filter

This paper proposes analytical expressions of a deadbeat control system for the output LCL filter in a grid-connected inverter with a settling time of three sampling periods. Unlike the conventional analysis, the proposed control algorithm is derived in the descritised time-domain instead of the s-domain. Furthermore, not only integrated active power but also reactive power can be controlled independently. Experimental results of the proposed deadbeat control system indicate that the feedback of both grid and converter currents have the same highest capabilities of attenuating switching frequency components and damping resonance. This is due to the undetected two remained control variables are possible to be estimated in the DSP.