An Optimized Hybrid FOPID+RMRAC Control Architecture for Grid-tied Inverters with LCL Filters

This paper presents a novel hybrid control architecture for grid-tied inverters with an LCL filter, combining a fractional-order proportional-integral-derivative controller, dedicated to reference tracking, and a robust model reference adaptive controller, employed for active rejection of grid disturbances. A systematic tuning procedure using the puma optimizer is provided to tune all eleven parameters of the composed control algorithm. Experimental results, performed on a TMS320F28335 Delfino microcontroller equipped in a laboratory prototype, corroborate the simulation findings, presenting fast current tracking and disturbance rejection, with low settling time and total harmonic distortion below the limits established by the IEEE 1547 standard, whose mean between the three-phases is 2.55% in steady state.