Power Electronic
N. Yousefi; D. Mirabbasi; B. Alfi; M. Salimi; Gh.R. Aghajani
Abstract
This report develops a high step-up topology employing a voltage multiplier cell (VMC) and a coupled inductor for renewable energy usage. The efficiency is improved and the blocking voltage on semiconductors is decreased. The proposed structure achieves a high voltage gain by utilizing a VMC and one ...
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This report develops a high step-up topology employing a voltage multiplier cell (VMC) and a coupled inductor for renewable energy usage. The efficiency is improved and the blocking voltage on semiconductors is decreased. The proposed structure achieves a high voltage gain by utilizing a VMC and one coupled inductor. This structure employs only one MOSFET switch, lowering the cost of the converter. Further benefits are the reduced number of components and the low blocking voltage of the switches/diodes. Furthermore, the VMC functions as a clamp circuit, reducing the peak voltage of the switch. Consequently, in the presented converter, a low nominal voltage MOSFET can be operated. The switching modes, steady-state analysis, and comparative study with other comparable converters demonstrate the converter's performance and superiority. A 200W laboratory scale operating under the 25kHz switching frequency and a voltage conversion of 20V~150V is built to validate the theoretical equations. The proposed converter efficiency at the full load is about 96.3%. Also, the normalized maximum voltage stress on switch and diodes for duty cycle D=0.6 and turn ratio N=2 is about 0.33 and 0.8, respectively.
Power Electronic
H. Shayeghi; R. Mohajery; N. Bizon
Abstract
This research introduces a modified design for non-isolated DC-DC converters with a high voltage gain using the design concepts of a coupled inductor (CI) and a hybrid voltage multiplier cell. It is attainable to further increase the output gain without requiring a higher duty cycle or a large turn ratio ...
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This research introduces a modified design for non-isolated DC-DC converters with a high voltage gain using the design concepts of a coupled inductor (CI) and a hybrid voltage multiplier cell. It is attainable to further increase the output gain without requiring a higher duty cycle or a large turn ratio of CI. This means that the power switch won't be under too much voltage stress. The suggested converter's important features are low maximum voltage across all semiconductor components, considerable efficiency, and a substantial voltage conversion ratio. In addition, the suggested topology includes diodes with soft switching conditions, which allows for a reduction in reverse recovery losses and an improvement in system efficiency. The proposed topology includes input current continuity, a single power switch, and a common ground between the source and the load. Operating analysis, theoretical definitions, efficiency investigation, and a literature review of comparable structures have been considered to demonstrate the proposed structure's functionality. An experimental prototype has also been established, featuring 115V output voltage, 20V input voltage, and 40kHz switching frequency, to facilitate the assessment of the proposed converter's efficacy.
H. Shayeghi; S. Pourjafar; S.M. Hashemzadeh; F. Sedaghati
Abstract
In this article, a novel topology of DC-DC converter based on voltage multiplier cell and coupled inductor with higher efficiency and low blocking voltage across semiconductor is proposed for renewable energy application. The recommended topology obtains a high voltage gain using voltage multiplier cell ...
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In this article, a novel topology of DC-DC converter based on voltage multiplier cell and coupled inductor with higher efficiency and low blocking voltage across semiconductor is proposed for renewable energy application. The recommended topology obtains a high voltage gain using voltage multiplier cell and one coupled inductor. Only one power switch is utilized in this structure, which reduces the converter's cost. The other benefits of this converter are low number of components, high efficiency due to the zero-voltage switching and the zero-current switching of diodes, and low blocking voltage of the power switch and diodes. Besides, the voltage multiplier cell acts as a passive clamp circuit and reduces the voltage stress across the power switch. Thus, a low rated power switch can be used in the presented topology. Due to the zero-current switching in Off-state, the reverse recovery problem of diodes is reduced. To illustrate the performance and superiority of the presented topology, operation modes, steady-state and efficiency analysis, and the comparison study with other similar converters are presented. Finally, a 160~W experimental prototype with 50~kHz switching frequency and 17 V input voltage are built to confirm the theoretical investigation and effectiveness of the proposed converter.
Power Electronic
M. Eskandarpour Azizkandi; F. Sedaghati; H. Shayeghi
Abstract
In this paper, a new high efficiency, high step-up, non-isolated, interleaved DC-DC converter for renewable energy applications is presented. In the suggested topology, two modified step-up KY converters are interleaved to obtain a high conversion ratio without the use of coupled inductors. In comparison ...
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In this paper, a new high efficiency, high step-up, non-isolated, interleaved DC-DC converter for renewable energy applications is presented. In the suggested topology, two modified step-up KY converters are interleaved to obtain a high conversion ratio without the use of coupled inductors. In comparison with the conventional interleaved DC-DC converters such as boost, buck-boost, SEPIC, ZETA and CUK, the presented converter has higher voltage gain that is obtained with a suitable duty cycle. Despite the high voltage gain of the proposed converter, the voltage stress of the power switches and diodes is low. Therefore, switches with low conduction losses can be applied to improve the converter efficiency. Moreover, due to utilization of interleaving techniques, the input current ripple is low which makes the suggested converter a good candidate for renewable energy applications such as PV power system. Operation principle and steady-state analysis of the proposed converter in continuous conduction mode (CCM) and discontinuous conduction mode (DCM) are discussed in detail. Also, theoretical efficiency of the proposed converter is calculated. Finally, in order to evaluate the proposed converter operation by a renewable energy source such as a PV, the simulation results are presented. Moreover, a 220W prototype of the presented DC-DC converter is designed and implemented in the laboratory to verify its performance.