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...

An improved single-ended push–pull (SEPP) halfbridge type zero-voltage soft-switching pulse width modulation (ZVS-PWM) DC–DC power converter is presented in this paper, which makes use of a saturable reactor-assisted lossless capacitor type zero voltage soft-switching method. The SEPP power converter with a high-frequency forward and flyback hybrid transformer link has some advantages such as l...

This paper proposes a high efficiency DC-DC flyback converter with a resonant full-bridge inverter to use in PV systems. The flyback converter is composed of a resonant active-clamp circuit that limits the voltage stress and provides zero voltage switching (ZVS) turn-on and turn-off of the power switches. Therefore, the switching losses of the high frequency primary switches are negligible. A r...

The controller is used to improve the dynamic performance of DC-DC converter by achieving a robust output voltage against load disturbances. This paper presents the performance of PI and Fuzzy controller for a phaseshifted zerovoltage switched full-bridge PWM (ZVS FBPWM) converters with a closed loop control. The proposed converter is regulated with minimum overshoot and good stability. In this...

A novel off-line zero-voltage-switching(ZVS) PWM A C D C converter for single stage preregulation in distributed power system is proposed. The proposed A W C converter provides both of input power factor correction and direct conversion from 110-220VAC line to 48VDC bus with single power stage. Comparing to the conventional two-stage approach(boost rectifier followed by off-line DC/DC step down...

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...

A numerical analysis of a Class D zero-voltage switching (ZVS) inverter in the time domain is presented along with experimental results. A discrete-time state-space approach is used for simulation. The state-space description and simulation results provide a fast insight into the physical operation of the converter. The algorithm is fast, easy to implement, and suitable for systems with high sp...

A novel zero-voltage-transition (ZVT) pulsewidth modulated (PWM) Cúk power-factor corrector (PFC) is proposed to achieve unity power factor under zero-voltage-switching (ZVS) operations. In the proposed ZVT PWM Cúk PFC, not only the power switch, but also the power diode, commutate under ZVS. The proposed topology has the shortest ZVT time and, thus, the shortest minimum duty cycle compared wit...

A passive lossless snubber cell is proposed to improve the turn-on and turnoff transients of the MOSFET’s in nonisolated pulsewidth modulated (PWM) dc/dc converters. Switching losses and EMI noise are reduced by restricting di=dt of the reverse-recovery current and dv=dt of the drain–source voltage. The MOSFET operates at zero-voltage-switching (ZVS) turnoff and near zero-current-switching (ZCS...

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, ...