High step‐up buck–boost DC–DC converter with coupled inductor and low component count for distributed PV generation systems

Abstract

This paper presents a non‐isolated high step‐up buck–boost with a coupled inductor DC–DC converter relevant for distributed photovoltaic (PV) generation systems. The proposed topology can reach high voltage gain through the combination of a buck–boost converter with a coupled inductor. The configuration of the proposed converter allows to achieve a natural voltage clamp circuit for the switch, recovering the energy stored in the leakage inductance of the coupled inductor. Moreover, the converter allows soft‐switching conditions, that is, Zero Current Switching (ZCS) for the diodes and nearly ZCS for the active switch. Also, the proposed converter presents a low component count and common ground connection of the input and output. The proposed converter is evaluated theoretically by the principle of operation in continuous‐conduction mode (CCM) and discontinuous‐conduction mode (DCM), voltage gain derivation, external characteristics, semiconductor voltage stress, current stress, and design guidelines. Finally, a 650‐W, 36/380‐V, 50‐kHz prototype was built in the laboratory to experimentally evaluate the proposed converter, which reached a maximum efficiency rate of 96.58%.

Theoretical and experimental evaluation of SEPIC‐based DC–DC converters with two‐winding and three‐winding coupled inductors

“…Regarding the differences between coupled inductors of proposed converter and the structure presented in Toebe et al, 10 the other comparison that can be made is calculating the sum of multiplied voltages and currents of windings. The voltage and current diagrams of the coupled inductors' primary winding are shown in Figure 6.…”

“…The second group of converters is based on coupled inductor that has been considered in recent studies 8 . In these converters, by adding a snubber and clamped circuit, the energy of leakage inductance can be recovered and transferred to the output and helps to prevent of the increasing voltage stress in the converter elements and increases the efficiency of the converter 9–13 . By combining the coupled inductor with some techniques, the voltage level can be increased significantly.…”

“…8 In these converters, by adding a snubber and clamped circuit, the energy of leakage inductance can be recovered and transferred to the output and helps to prevent of the increasing voltage stress in the converter elements and increases the efficiency of the converter. [9][10][11][12][13] By combining the coupled inductor with some techniques, the voltage level can be increased significantly. These techniques include voltage lifting, 14,15 voltage multiplier, [16][17][18][19][20] switched capacitor, 21,22 and switched inductor.…”

An Extensive Critique on Electric Vehicle Components and Charging Systems

“…e major limitation of the proposed bidirectional converter is the leakage inductance. e presence of leakage inductance leads to voltage swell and resonance in the circuit [95]. e authors in [94] implemented the coupled inductor-based bidirectional converter for controlling the DC voltage of an electric vehicle.…”

Modular DC‐DC converter with reduced current ripple and low voltage stress suitable for high voltage applications

“…The high gain coupled inductor (CI)‐based dc‐dc structures provide the turn ratio of windings as an additional degree of freedom alongside duty cycle of main switches 17–19 . However, it is necessary to apply a clamping circuit in order to eliminate the voltage spikes upon their power switches generated by the presence of their leakage inductances 20,21 . The voltage multiplier (VM) is the most commonly used technique to boost the output voltage, which can be categorized into two types: voltage multiplier cell (VMC) and voltage multiplier rectifier (VMR) 5 .…”