Operating-Point-Shifting Based DAB Talkative Power Conversion

Talkative power conversion (TPC), which can modulate and transmit power and data simultaneously by embedding the data into the power process with zero additional hardware cost in the transmitter side, is an emerging technology for digital energy, internet of energy, cyber-physical system and smart grid applications, where the system is dominated by high penetration of power electronics converter-interfaced resources. Frequency-shift keying (FSK) is a common technique to achieve TPC for the dual-active bridge (DAB), but the variation of switching frequency challenges not only the system operation efficiency but also the design of the filter and inductive components. Hence, to overcome the drawback of FSK, this paper proposes a novel TPC technique for DAB by shifting two operating points that transmit the same power in the power-phase curve of DAB and keep the switching frequency constant. The dynamic performance has been optimized by accurately controlling the phase-shift-point of DAB. The modulation is simple compared to state-of-the-art talkative DAB techniques. The simulation and experimental results clearly validate the effectiveness and feasibility of the proposed talkative DAB technique.