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Here, a high gain DC–DC converter which is based on switched capacitor (SC) and switched LCL (SLCL) cells is presented. The diode employed in the classical passive switched inductor (SI) cell is replaced by a capacitor in the proposed SLCL cell to achieve higher voltage gain. Two switches—one each in the positive and negative DC rails of the supply are employed to charge and discharge the inductors of SLCL cells. A generic structure comprising of N and M number of SLCL cells in the positive and negative DC rails respectively along with K number of SC cells is presented. To validate the proposed gain extension concept, a two‐switch based converter comprising of 2 SLCL and 1 SC cells is synthesized and its operation is described in detail. The voltage gain expression of the proposed SLCL‐SC converter is derived. Experimental results are obtained from a 25 to 380 V prototype converter which operates at a full‐load efficiency of 94.22% at 200 W. Since the switches employed in the proposed converter are operated at a moderate and safe duty ratio of D = 0.51, the voltage stress on the switches is about 25% of the output voltage while the diodes are subjected to even lesser voltage stress levels of only one‐fifth of the output voltage. The main salient features of the proposed topology are its (i) modular structure, (ii) ability to provide higher voltage gain values at lower duty ratios (iii) reduced voltage stress on the semiconductor devices and (iv) reduced conduction losses due to the replacement of diodes with capacitors in SLCL cells.

This study presents a family of novel high gain non-isolated hybrid dc-dc converter for dc micro grid application. The proposed family of the converter is developed by employing both inductor-capacitor-inductor (LCL) based switched inductor (SI) and switched capacitor (SC) technique to achieve high voltage gain. Appropriate increase in the number of LCL-based SI cells in the power circuits in order to achieve ultra-high voltage gain allows formulating a generalised structure of the circuit. Incorporation of SI & SC techniques and the structure of the circuit with one stage power transfer ensure high voltage gain at low voltage stress across the switches and diodes. The study includes the principle of operation, steady-state analysis and performance analysis in detail for the converters. Experimental results from the developed hardware prototype of 380 V/250 W validate the adopted concept, design and exemplify that the proposed family of converter operates at a full load efficiency of 94%.

In recent years, DC microgrid integrated with energy sources like solar PV, fuel cell, and batteries receives tremendous attention due to the depleting fossil fuel reserves, massive urge to reduce carbon footprint, and initiatives for decentralized power distribution policy. It is essential to connect an intermediate DC-DC converter between these low voltage sources and grid. This paper presents an ultra-high gain non-isolated DC-DC converter for DC microgrid system integrated with fuel cell. This converter is developed by judicially combining both switched inductor (SI) and switched capacitor (SC) techniques as gain extension network. Integration of these techniques in the adopted circuit for ultra-high voltage gain evolves into a hybrid modular structure with extendable gain options. This paper includes circuit diagram, operation, design procedure, and results of the proposed hybrid SI-SC (HSISC) converter. Results available from the hardware model of 380V/200W validate the performance of the converter at an efficiency of 92.23%.

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