Implementation and validation of DQ current control of a bidirectional SiC single-phase AC-DC converter

Electric vehicles (EV) have the potential to revolutionize the transportation sector in the next decade. Electrical energy stored in the EV remains unusable while parked. This electrical energy collectively can be utilized as an ancillary service to the grid during peak demand. This necessitates the EV battery charger to be bi-directional, capable of sinking or sourcing real and reactive power. A modulation strategy for DQ (direct-quadrature axis) current control of a bi-directional dual active bridge (DAB) based AC-DC converter is analyzed. Simulation results are presented with sinking or sourcing real and reactive power into the AC grid. Hardware and firmware implementation of a single stage, bi-directional AC-DC converter for a single phase 3-wire system (240 V, 6.6 kW) operating at 100 kHz switching frequency utilizing Silicon Carbide (SiC) MOSFET is discussed. Experimental results are shown with input current free of harmonic distortion.