Zero-current (ZC) switching pulse-widthmodulated (PWM) flyback DC-DC converter is an extended version of the single switch flyback converter with an additional active circuit. The purpose of the active circuit is to turn-off the main switch with zero-current switching (ZCS) condition to reduce the turn-off switching loss. This paper presents an overview of the ZCS flyback PWM DCDC converters. T...

In this paper, a new bidirectional buck-boost dc-dc converter with capability of soft switching and zero input current ripple is proposed. The coupled inductor is used in the proposed converter to eliminate the input current ripple. In the proposed converter, zero voltage switching (ZVS) and zero current switching (ZCS) can be obtained for the main and auxiliary switches, respectively. In addit...

In this paper, based on the switching cell approach, a unified steady state analysis for families of soft-switching dc–dc converters with complete unified design equations will be presented. The concept of the unified approach and step by step procedure for a generalized process are discussed and applied to selected soft-switching families such as zero-voltage-switching (ZVS) and zero-current-s...

This paper introduces a new soft switching boost converter with passive snubber. In the proposed converter, the main switch turns on under zero current switching (ZCS) and turns off under zero voltage switching (ZVS) without any additional voltage or current stresses. The main diode turns on under ZVS and turns off under ZCS. The proposed converter has features as low cost, simple control, low ...

This paper proposes two new soft-switching transformerless converters with high voltage conversion ratio. These proposed converters achieve soft-switching each with a single auxiliary resonant cell. The merit of these converters is reduced switching losses with lesser number of devices. The main switching devices are turned off with zero current switching (ZCS). Apart from the soft-switching fe...

This paper proposes a novel phase-shifted zerovoltage and zero-current-switching (ZVZCS) pulsewidth modulation full-bridge converter, which realizes ZVS for the leading leg and ZCS for the lagging leg. A blocking capacitor is added in series with the primary winding of the transformer to make the primary current decay to zero during zero state to ensure ZCS for the lagging leg. In order to prev...

A novel interleaved boost and buck converter with zero-voltage switching (ZVS) and zero-current switching (ZCS) characteristic is proposed in this paper. By using the interleaved approach, this topology not only decreases the current stress of the main circuit device but also reduces the ripple of the input current and output voltage. Moreover, by establishing the common soft-switching module, ...

An improved active snubber cell is proposed for ZVT-ZCT PWM DC-DC boost converter. Zero voltage transition (ZVT) turn on and zero current transition (ZCT) turn off is provided by this active snubber cell. There is no extra current or voltage stresses on the main switch. Also, zero current switching (ZCS) turn on ZCT turn off is provided for the auxiliary switch. Although there is no extra volta...

This paper presents a new family of pulsewidthmodulated (PWM) converters, featuring soft commutation of the semiconductors at zero current (ZC) in the transistors and zero voltage (ZV) in the rectifiers. Besides operating at constant frequency and with reduced commutation losses, these new converters have output characteristics similar to the hard-switchingPWM counterpart, which means that ther...

An Isolated ZVS/ZCS bidirectional DC-DC converter for DC Uninterruptable Power supplies is presented in this paper. The usual way to avoid a computer shutdown during the mains failure is to connect an ac uninterruptible power supply (UPS). Alternatively, in this paper, a simple and high efficiency dc UPS is presented by an isolated bidirectional soft-switching dc-dc converter. The bidirectional...