Also, a massive turn-off voltage spikes in the power switch is generated due to the leakage inductance, which results in additional voltage stress on the components that require a snubber circuit to clamp the switch voltage resulting in a bigger size and more expensive. They have also a limited range of increasing the voltage level besides higher voltage stress. However, they suffer from numerous restrictions which reduce their efficiency, reduce performance in high step-up applications, and make the system more complicated and bulkier. Full-bridge, half-bridge, fly back, forward, and push–pull converters are used at various voltage and power levels 11, 12, 13, 14 where isolation is needed. The use of high-frequency transformers can increase the voltage gain as well as isolation, and then, full-bridge-based topologies can be used 10, but with limited power capability, higher losses, lower efficiency, and higher cost. However, they have some problems such as higher losses, lower efficiency, electromagnetic interference problems, and reverse recovery problem. In switched-capacitor-based converters 4, 5 and switched capacitor/switched inductor-based converters 6, 7, 8, 9 high-voltage gain with small duty cycle, small voltage stress across the switches can be attained, and these converters can be used in a wide range of power. But, it has higher losses, lower efficiency, and electromagnetic interference problems. In 3, cascaded boost converter has been successful in solving some of the problems appeared with conventional boost converter as it can attain a reasonable high voltage gain without working at extreme duty cycle, and the voltage stress through the switches remains lower than the voltage across the load. That causes a high-semiconductors voltage stress, diode reverse recovery problems, and high switching loss which decrease the system performance and efficiency. But it provided a limited practical gain because of their parasitic elements and must be operated at an extreme duty cycle in order to obtain high voltage gain. To obtain the voltage step-up function, a conventional non-isolated DC/DC boost converter was used 2 because of its simple structure, simple control, and low cost. The power electronic interface specification is dependent not only on the renewable energy supply but also on its effects on the power-system operation 1. The unregulated low-level DC output voltage from these sources is considered the biggest and the most important challenge that requires to be boosted to a regulated higher level using power electronic conditioning. Scientists have been interested in renewable energy sources such as photovoltaic (PV) to produce electricity because they appeared to be the most efficient and effective solution to the environmental problems that the world faces today. Experimental results in an open and closed-loop, and a comparison with other recent converters are also introduced to confirm the validity of the proposed converter. To prove the converter’s effectiveness, theoretical analysis, project specifications, and operation principles are presented and studied. These features make the converter a good choice for many applications such as photovoltaic, x-ray, fuel cells, etc. Moreover, the converter operates with a continuous input current. Operating the converter in DCM can support a wide range of the duty cycle operation, maintain lower voltage stress of all devices, ensure the same current sharing among inductors, make it easy to control, provide more stability, and require a smaller inductor which reduces size and weight of the proposed converter. Wide duty cycle range operation, high output voltage gain, low switching stress, small switching losses, and high efficiency are achieved efficiently. The proposed converter operates in discontinuous-current mode (DCM) with zero current switching for all switches and diodes. In this paper, a new design of a non-isolated high-voltage gain DC/DC converter that operates at a reasonable duty cycle, by merging the dual boost converter with the switched inductor structure, is presented as a solution for the high-conversion ratio requirement.
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