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This paper proposes, a novel soft‐switching bidirectional direct current to direct current (DC–DC) converter based on switched‐capacitor and coupled‐inductor. The proposed converter has a simple structure and utilizes four switches and a three‐winding coupled inductor and can achieve a high voltage conversion ratio in both step‐up/step‐down operations. By employing the switched‐capacitor technique, voltage stress across the power switches is low and therefore low voltage rating switches can be adopted to reduce the losses of their conduction. Soft‐switching characteristic of the proposed converter reduces the switching loss of active power switches and raises the conversion efficiency. This paper presents theoretical analysis for all operating modes of the converter, voltage conversion ratio, voltage and current stresses of all power switches. Finally, to test the validity of theoretical results and demonstrate the performance of the converter, experimental results are provided. [ABSTRACT FROM AUTHOR]

This paper proposes a switched Z‐source inverter with high voltage gain and low current stress on elements. Also, a new switching method corresponding to the proposed topology is introduced. This method is based on the usual Maximum Constant Boost (MCB) method. Hence, it has the advantages of the MCB method, such as low voltage stress on the inverter switches and high voltage gain. Also, eliminating part of the inverter's switching in this modulation method improves the inverter's efficiency. In addition to the Shoot‐Through (ST) duty cycle, another variable (N) affects the inverter's boost factor in this switching method. The proposed inverter's dynamic analysis shows that introducing N in the modulation method improved the dynamic characteristic of the inverter. Also, this variable as a control input can stabilize the dc side of the inverter in the closed‐loop control of the inverter. For the proposed topology, steady‐state analysis, dynamic analysis, elements design and efficiency calculation are performed. Also, the proposed topology is compared with the conventional topologies regarding boost factor, the number of elements, current stress on elements and efficiency to show its superiority. Finally, the experimental results are presented to verify theoretical discussions. [ABSTRACT FROM AUTHOR]

In this article, two compact three-phase multilevel inverters are proposed. The first proposed topology consists of three dc sources and ten power switches. The merit of the first proposed topology is reducing two switches from its structure to the conventional topologies. The second proposed topology is similar to the first one, except that one of the dc sources is replaced by a capacitor. This capacitor is balanced by an additional switch and one of the dc sources. How to apply two modulation methods for these inverters has been studied in detail. These modulation methods are level-shifted pulsewidth modulation and phase-shifted pulsewidth modulation (PS-PWM). Also, the value of the capacitor for each of the modulation methods has been calculated. Finally, the experimental results are provided to confirm the performance of the proposed topologies. [ABSTRACT FROM AUTHOR]