Study and analysis of a DC–DC soft‐switched buck converter

Abstract

In this study, a soft-switched buck converter is proposed and analysed. In this structure, by adding an auxiliary inductor and two auxiliary capacitors, zero-voltage switching condition for switch's turn on and near to soft-switching condition for switch's turn off are provided. Furthermore, the power diode turns off under zero-current switching condition. As a result, switching losses and reverse recovery losses have been eliminated, and the proposed converter can provide high efficiencies. To prove the mentioned advantages, a 200 W laboratory prototype of the proposed converter is built and its results are investigated completely. On the basis of these results, the proposed converter can provide 96.1% experimental efficiency at 200 W output power, which proves the 96.78% theoretical efficiency. Also, in comparison results, it is shown that this converter not only provides higher efficiency in comparison with other structures, but also it has less components and simpler structure than other related buck converters.

Novel Zero-Voltage Zero-Current Transition Buck Converter With Minimal Impact of Active Auxiliary Cell on Overall Dynamics

“…The size and weight of magnetic and filter components of the power converters can be reduced by many folds with high switching frequency operation, but at the cost of excessive switching loss, increased current and voltage stress of semiconductor elements, large RFI &EMI, if operated with conventional hard switching. Extensive research works [1][2][3][4][5][6][7][8][9][10][11][12][13][14], [22], [25] are therefore carried out to minimize above issues by adopting softswitching transition of semiconductor switches. To meet the demand of modern applications, major research has been carried out in recent years to develop new topologies of softswitched buck converters.…”

“…The interleaved structure [5][6] can provide high step down ratio as well as low ripple content at the load current. In [7][8] soft turn on is obtained by triggering the gate pulse when the body diode of the switch is in conduction making the voltage across the semiconductor switch zero.ZVS transition is achieved by utilizing the leakage energy of the coupled inductor with the aid of an auxiliary network consists of an inductor, a switch and a diode in [9].Switched capacitor network [11] or voltage multiplier cells [12] or a combination of switched capacitor and coupled inductor [1][2][3][4], [11][12] have been used in many buck converters to extend the voltage gain. In [14], a switched inductor network is used for step down purpose.…”

Forward converter using a resonant auxiliary circuit to provide soft‐switching and reset the magnetic core

“…Increasing efficiency and reducing the converter weight and size is the most significant factors in evaluating and comparing different topologies [3]. Reducing the converter weight and size is achieved predominantly by rising the switching frequency due to the negative correlation between the converter passive components size and the switching frequency [4,5]. At high switching frequencies, soft-switching operation is inevitable in order to mitigate frequency-related losses.…”

New auxiliary circuit for boost converter to achieve soft‐switching operation and zero input current ripple

“…Nowadays, DC–DC converters play an important role in renewable energies interfaces [1–5] where the boost converters as a common type are implemented to increase the DC voltage range. Due to their simple structures, boost converters are used in power factor correction applications too [6].…”