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In this study, a new bipolar DC-DC converter based on the combination of a multi-port dual active bridge and a neutral point clamp topology is proposed. This topology provides the integration of multiple renewable energy sources, with different types and capacities, to a bipolar medium voltage DC micro-grid. The main advantages of the proposed topology are its high power density and the reduced number of switches with respect to the combination of different converters. Moreover, it provides isolation which is crucial for some micro-grid power conditioning converters. The proposed converter is employed for a typical hybrid generation system consisting of a photovoltaic (PV) system, a fuel cell (FC), and a battery (BAT) considering the characteristics of each power generation system like maximum power point tracking of PV, optimum operating region of FC and over-charge/discharge of BAT. In addition, the proposed converter is simulated in different power sharing modes in MATLAB/ Simulink software environment. Eventually, the theoretical and simulation analyses are validated by experimental prototype results.

In this paper, a new interleaved DC-DC converter based on a coupled and a single input inductor is proposed. The suggested high step-up converter utilizes various inductive and capacitive methods to transfer magnetic energy more efficiently. The output voltage is regulated with the switches' duty cycle and the coupled inductor (CI) turns ratio, which provide a wide output voltage range. Interleaving improves the converter reliability, employs both the first and third areas of CI's B-H plane, cancels DC component of the CI, and reduces the input current ripple of the proposed converter with twice switching frequency. Utilization of two output ports for voltage stress and ripple reduction in each port, recycling the stored energy of inductances in both forward and flyback mechanisms, alleviation of switch voltage spikes, operation without circulating current, high power density, independency of switch voltage stress to the CI turns ratio, and continuous input current can be mentioned as other features. In this paper, continuous and discontinuous conduction modes' steady-state analytics, power loss calculations, and design procedure of the proposed converter are followed with comprehensive comparisons to evaluate the capabilities. Eventually, experimental results are presented to validate theoretical calculations.

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In this study, a new isolated high-gain switched-boost DC/DC converter employing two symmetrical switched-boost networks along with a modified control algorithm based on the combination of the pulse-width modulation (PWM) and phaseshift modulation is proposed. Utilising symmetrical switched-boost networks increase the voltage gain of the proposed converter, significantly. Moreover, applying the proposed switching algorithm on the proposed isolated switched-boost DC/DC converter leads to the following advantages: (i) high-voltage gain, (ii) zero voltage switching (ZVS) turn-on of two switches, (iii) ZVS turnoff of two switches and (iv) appearing three controllable parameters (the shoot-through duty cycle, the phase shift and the transformer turns ratio) in all of the equations including the voltage gain equation, which enhances the flexibility of the converter. In this study, the steady-state analysis, design procedure of the elements, and voltage and current stress of the semiconductors are given. Then, the proposed converter and the proposed switching algorithm are compared with similar converters and modulation techniques in order to highlight their features and drawbacks. Finally, experimental results are obtained to substantiate the theoretical analysis accuracy.

<p> This paper provides a practical guideline for conductor arrangement in a planar inductor by investigating various arrangements for conductors. In order to have a comprehensive study, four different structures have been considered and compared. Numerous design parameters such as track width, track length, location of the conductors between the central limb and the lateral limb, and number of transposition points among sub-tracks for both air-core and ferrite-core inductors are considered. Each structure is evaluated according to AC resistance, RAC /RDC, and inductance. Measurement results reveal that it is critical to take into account all three characteristics when deciding the suitable structure for the conductors. Studies are carried out based on measurement results for experimental prototypes in the frequency range of 10Hz-1MHz and a set of guidelines has been provided with regard to the design of planar inductors to achieve desired characteristics. </p>

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The design of gate drivers is an important topic in power converter topologies that can help reduce switching losses and increase power density. Gate driving techniques that offer zero-voltage switching and/or zero current switching have recently been successfully proposed for different modular multilevel converters such as the cascaded H bridge. Previous papers on other multilevel converters such as the multi-active bridge, however, do not sufficiently assess the topics of gate driver design for this topology. This work presents a novel isolated gate driver architecture tailored to the multi-active bridge topology. Zero voltage switching is then achieved using two multi-winding transformers. The advantages of the proposed topology are not only a reduction of switching losses but also reduced component count. The topology is evaluated on a prototype using experimental results. It was shown using simulation and experiments that the proposed topology has a high efficiency while providing compact power packaging. Especially for converters with many levels, the proposed topology is therefore advantageous compared to existing solutions.