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...

An asymmetrical pulse width modulated (APWM) dc-dc converters operating at constant frequency was simulated using Pspice software package. This converter incorporates constant frequency operation in a basic soft switching half bridge topology without any additional component and complexity. In this paper operation of converter configuration with capacitive filter in the output is discussed. A 5...

The model of the new zero-voltage and zero current switching energy recovery display driver for a Plasma Display Panel is proposed. This operation helps to achieve the zero-voltage turn on of all main power switches and zero-current turn-off of all auxiliary power switches, reduce the EMI noise, current stress in Mode 2 and Mode 3 operation, and improve the energy recovery capability. This pape...

This paper presents a novel three-phase power factor corrector (PFC) circuit which uses two power switches working in zero-voltage-switching (ZVS) condition. The two switches along with a high-frequency inductor constitute a high-frequency current source which is responsible for the energy transfer in the circuit. The input current is partly continuous and partly discontinuous. The total harmon...

A single phase ac-dc soft switched PFC converter with a LCD snubber is presented for dc output voltage regulation. The LCD snubber cell provides zero current switching (ZCS) turn ON and zero voltage switching (ZVS) turn OFF for the converter switch without increasing current or voltage stress. In this study, steady state analysis of proposed PFC converter is presented in detail and the theoreti...

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...

Abstract– In this paper, a detailed analysis of the zerovoltage and zero-current-switching (ZVZCS) full-bridge PWM converters is performed. The differences of the zero-voltage-switching (ZVS) operation between the conventional ZVS full-bridge PWM converters and the ZVZCS full-bridge PWM converters are analyzed in depth. Circuit parameters that affect the soft-switching conditions are examined a...

In the present paper a simple sensorless spccd estimation scheme is presented , where the speed information is obtained from the motor phase current ripple. The scheme measures the stator current phasor deviation direction to determine the back emf vector position during inverter zero vector switching states. This measurcment of rotor flux position is done indirectly by computing the motor back...

---------------------------------------------------------------------***--------------------------------------------------------------------Abstract In AC to DC converters, power factor has significant importance. Most power converters and equipments are developed to have power factor correction technology to improve their performance. A soft-switching two-switch resonant ACDC converter with hi...

A soft-switching topology for high power buck converter is proposed. Zero-current turn-on and zero-voltage turn-off is achieved without auxiliary switches. All active switches in the converter transmit power to the load equally. Converter control is simple despite four active switches. Converter operation is described and DC analysis is carried out. All operation modes are identified. The condi...