In this article, we present a fully distributed optimization approach for real-time energy management of dc microgrids. In the proposed approach, the energy management system (EMS) is formulated with a consensus algorithm based on incremental cost, which operates in a distributed manner for both generation and demand-side management. The proposed algorithm is privacy-preserving, scalable, plug-and-play capable, and robust against time-varying communication topologies. Furthermore, it converges very fast in terms of computation time and iterations. The scalability of the proposed algorithm was evaluated using IEEE bus systems in various sizes, number of agents, and communication topologies. A cooperative multilayered EMS optimally coordinated by multiple agents was also proposed in this article for integration. The effectiveness of the proposed system was validated through computer simulations and hardware experiments.

Electromagnetic radiation from 3 Hz to 30 kHz in the ELF/ULF/VLF bands sees continued and even renewed interest, despite significant engineering challenges in creating portable radiation systems in this frequency range. A novel mechanical shutter-based antenna with fixed permanent magnets is presented that allows for broadband radiation from a handheld source without the excessive mechanical requirements that have made traditional mechanical antenna concepts impractical. The validated prototype is a mechanical alternative to an electrically short antenna.

DC microgrids with power electronic converter units are prone to become unstable due to the well-known negative impedance characteristic of constant power loads. For such systems, the global stability cannot be assumed. It is known that the transient stability of the system can be degraded by large and fast disturbances due to the reduced stability region. As a result, the system gets to operate outside the stability region and becomes unstable even if the steady-state operating point is in the stable region. To overcome this problem, a dynamic stabilizer that controls the stability region using variable inductor is proposed to guarantee stable operation during transient-states. The proposed scheme is straightforward and can be implemented with minimal power consumption. Furthermore, it is robust for parameter variation. The feasibility of the proposed method is verified experimentally.

This paper introduces a dual-switchhigh step-up DC-DC power converter. The proposed converter features a high step-up voltage gain, relatively low cumulative stored energy over its inductors, low voltage stress on the active switches, and high efficiency, even at a relatively high duty ratio. An assessment of the proposed converter against conventional boost and a high step-up power converter is presented in terms of steady-state time, voltage gain, stored energy over its inductors, and efficiency. The assessment shows a reduction of 81.25% and 62.5% of stored energy in inductors to comply with the same operational conditions. Simulation and experimental results are provided to validate the benefits of the proposed dual-switch high step-up power converter.