Four papers at the AEIT International Annual Conference

The paper entitled “Operation schedule of DC microgrid for EVs with reserve under various conditions”, the paper entitled “Reduction of Output Capacitance for DAB DC-DC Converters in DC Microgrids by Shaping Resistive Output Impedance”, the paper entitled “Triple-Phase Shift Modulation for Dual Active Bridge based on Simplified Switching Loss Model”, and the paper entitled “Regaining Insight and Control on SMGW-based Secure Communication in Smart Grids” have been published in the proceedings of the 2019 AEIT International Annual Conference!

In the first paper the analysis of different technical and economic conditions influencing operation schedule and reserve provision for a realistic DC microgrid with EVs are analyzed by means of a proper optimal programming procedure.

The second paper proposes a design methodology for droop-controlled Dual Active Bridge (DAB) dc-dc converters, so that the resistive output impedance can be achieved. This design approach consists of the selection of output capacitance and the design of droop controller. Besides, for converters with small output capacitance, the output voltage presents high switching ripple. In such a case, the traditional single sampling technique causes a steady-state error between the averaged output voltage and the sampled one, impacting on the output impedance. This issue is addressed in this paper by a hybrid sampling method which combines the instantaneous value and the well-filtered value of the output voltage. Finally, the proposed design method with the hybrid sampling method is verified by experimental results.

The third paper proposes and analyzes triple phase shift modulation techniques aiming at maximizing the efficiency of the dual active bridge (DAB) converter. The DAB converter finds natural application in smart dc power systems integrating renew-ables and energy storage systems, for which loss minimization is crucial. This paper shows that the investigated modulation schemes allow converter efficiency improvements by exploiting complete or partial zero-voltage switching in a range of operating conditions as wide as possible, similarly to other papers in the literature based on triple phase shift modulation. Distinctively, the approach presented herein is based on simple converter modeling and the characterization of the switching elements. Experimental results are reported showing the performance attained by the proposed techniques considering a 1.5- kW converter prototype.

Finally, the forth paper presents mechanisms that enable local devices to regain this insight and control over the full connection, i.e., up to the final receiver, while retaining the SMGW’s ability to ensure a suitable security level. The evaluation shows modest computation and transmission overheads for this increased security in the critical smart grid infrastructure.