Ultra‐high gain DC‐DC converter based on interleaved quadratic boost converter with ripple‐free input current

Abstract

Background In this paper, an ultra‐high gain DC‐DC converter (UHGC) which provides a very high voltage conversion ratio value of 21.11 is described. Methods The proposed UHGC is synthesized from a two‐phase interleaved quadratic boost converter (IQBC). The voltage gain of the IQBC is further extended by using the voltage‐lift technique. To meet the standard DC voltage level of 380 V across the load terminals, the output of the voltage‐lifted IQBC is cascaded to a conventional boost converter (CBC). By operating the switches located in the IQBC stage with a duty ratio of 0.5 and 180° phase‐shift, the source current ripples are nullified. Besides drawing a smooth and ripple‐free current from the input, the converter's voltage gain is adjusted by varying the duty ratio of the switch employed in the CBC stage. Results The proposed gain extension concept is practically validated by conducting experiments on 18‐380 V, 150 W prototype converter. Under practical conditions, the proposed converter operates at full‐load efficiency of 94.7%. Moreover, due to the proposed gain enhancing technique, the two switches employed in the IQBC stage are subjected to low voltage stress levels which are 18.95% of the output voltage. By employing a simple closed‐loop control technique, the output voltage is regulated to remain constant at 380 V despite variations in line voltage and load current magnitudes. Conclusion The proposed UHGC possesses some advantageous features like (i) high voltage gain capability, (ii) ability to draw smooth and continuous (ripple‐free) current from the input, (iii) flexible structure which provides the required high voltage gain while drawing smooth current from the source and (iv) ability to quickly regulate the output voltage using simple closed‐loop control. Thus, the proposed UHGC is an appropriate choice for integrating the input PV source to a common DC bus or microgrid.

Non-isolated high gain DC–DC converter with ripple-free source current

“…The converters presented in 23 yield high voltage gain values besides drawing ripple-free input current. The converters presented in 24 , 25 , 28 use three and two CIs in an interleaved configuration. Their input current ripple is also negligible.…”

A New Continuous Input Current Nonisolated Bidirectional Interleaved Buck-Boost DC-DC Converter

“…e used battery in renewable sources can be charged using a bidirectional converter and discharged in low and high loads, respectively [1][2][3][4]. In applications such as fuel cells, electric vehicles, and power factor correction, to increase the system's life, it is necessary to have a converter with a continuous input current with a small ripple [5][6][7].…”

New family of transformer‐less quadratic buck‐boost converters with wide conversion ratio

“…The converters presented in Refs. 25‐28 have reduced current and voltage ripples at input and output, respectively, but require high‐voltage capacitors. For the same quadratic voltage gain, the converter 29 is presented for continuous input and continuous output current by cascading boost, buck‐boost, and buck converter and is reduced to a single switch topology.…”