Transformerless high‐gain DC–DC converter for microgrids

Abstract

This study proposes a novel non-isolated high-gain high-power DC-DC converter. The converter is developed from a basic high-gain high-power converter structure. The proposed converter comprises of a three-phase interleaved boost converter, one coupled inductor and a voltage multiplier cell which act as gain extension stage. The main desirable features like voltage gain, stress on the switches and diodes, turns ratio, component utilisation factor and efficiency are summarised. The power circuit, operational details, simulation and experimental results of the 60 V/1.1 kV, 3 kW, 100 kHz proposed converter are presented.

High step‐up high step‐down bidirectional DC/DC converter

“…+ I m22 (11) where I m12 and I m22 are the values of i Lm1 and i Lm2 at moment t 0 , respectively. Considering (10) and Fig. 3a, the transferred current of i C to primary side of transformer…”

“…These converters have unidirectional power flow. In [7][8][9][10][11][12][13] several interleaved highvoltage gain boost dc-dc converters have been presented. The interleaved converters decrease the input current ripple.…”

“…The voltage gain of this converter is lower than the presented converters in [7][8][9][10][11][12]. The presented interleaved converters in [7][8][9][10][11][12][13] achieve high-voltage gain for duty cycle >0.5. In [14], a high-voltage gain converter has been presented.…”

“…In this converter by using one three-winding coupled inductor and diode capacitor circuit, voltage gain is increased. All of presented converters in [7][8][9][10][11][12][13][14] are unidirectional converters. The bidirectional dc-dc converters are divided into two groups of isolated and non-isolated converters that non-isolated converters have losses lower than isolated converters [15,16].…”

Effective combination of quadratic boost converter with voltage multiplier cell to increase voltage gain

“…Recently, new structures have been presented which include increasing voltage gain methods [7][8][9]. The used methods add advantages and disadvantages to the proposed structures that make them proper for definite applications.…”