Control of Parallel-connected AC to DC Converter with Droop Technique for DC Microgrid Application

摘要

This paper presents the control of a single-phase ac to dc converter using the rotating reference frame control methodology wherein the phase angle (p) obtained from a single-phase phase-locked loop is used for axis-transformation. The I_d, I_q currents and output voltage of the converter are then confrolled by PI confrol strategy. The dc microgrid under study consists of two modules of the ac to dc converters connected in parallel topology using droop confrol technique. The simulation results based on Matlab/Simulink illusfrate that I_d, I_q currents can be regulated by the designed PI controllers. Therefore, zero steady state error and simple power calculation are achieved. Also, real power sharing between the two converters is fulfilled by the parallel-connected converter topology with droop confroller in such a dc microgrid system, while the output voltage is maintained at 600 V by a PI confroller at the secondary confrol level.