Regenerative switched‐inductor/capacitor type DC–DC converter with large voltage gain for PV applications

Abstract

In grid-connected PV applications, the presence of a transformer not only increases the cost, size and weight, but also decreases the whole system efficiency, especially, under poor irradiation conditions. To eliminate the transformer and to meet DC link voltage, a regenerative switched-inductor/capacitor type DC-DC converter with large voltage gain is proposed in this study. In traditional boost type and derived converters, the voltage gain ratio is limited due to voltage stress on the semiconductor devices and low efficiency because of more components count and large duty cycle operation. The proposed converter recycles the energy in lossless passive components and increases the step-up voltage gain, which improves the efficiency. In addition, the converter possesses fewer ripples and smooth continuous current, which reduces the power loss, elongates lifespan of the input source and restricts electromagnetic interference issues. This study presents detailed operating waveforms, modes of operation and performance characteristics of the proposed converter. In order to validate the operation, 500 W experimental prototype is developed and verified with measured results. The proposed converter yields the peak efficiency of 95.20% for the output power of 440 W.

A high step‐up dc‐dc converter based on P‐impedance source with reduced voltage stress

“…Another group of step‐up converters is switched‐inductor (SL) circuits that their operation is similar to SC circuits. However, these are involving many inductors that store magnetic energy 19–23 . Utilizing transformers and coupled inductors is also another solution for step‐up dc‐dc conversion 24–28 .…”

“…However, these are involving many inductors that store magnetic energy. [19][20][21][22][23] Utilizing transformers and coupled inductors is also another solution for step-up dc-dc conversion. [24][25][26][27][28] Higher gains are achieved due to the transformer/coupled inductor winding coefficient.…”

An innovative interleaved high step‐up direct current–direct current converter with switched‐inductor/capacitor–diode units for hydrogen fuel cell power system

“…Faridpak et al 35 added passive switched inductor, active switched inductor, and switched capacitor cells to conventional boost topologies, whose results indicated that its voltage gain and efficiency could be improved by utilizing the above structures. Karthikeyan et al 36 put forward a regenerative switched‐inductor/capacitor type DC–DC converter with large voltage gain, whose results indicated that this topology possessed smooth continuous current and the energy in lossless passive components could be recycled. Elsayad et al 37 presented a single‐switch transformerless boost DC–DC converter, which was composed of a switched‐capacitor multiplier and an integrated LC 2 D output network, and it could be seen that this structure had a wide voltage gain range to suit the wide voltage swings of fuel cells.…”

SiC‐based high‐gain DC–DC converters with fault ride‐through capability

“…The converter utilises more components. Later, different converter topologies are described to attain high‐voltage gain based on the modified SL and SC networks [7–9]. Recently, a converter topology using nine components is also reported to achieve the voltage gain of (1 + D )/(1 − D ) [10].…”