A full-bridge CLLL DC/DC converter that uses an auxiliary circuit is proposed in this paper. The soft switching of lagging leg and auxiliary switches is achieved by the proposed circuit for providing reduced switching losses and high efficiency. The theoretical detail operation of the converter is presented. The proposed converter is verified using MATLAB simulation. Closed loop and open loop c...

In this paper, it is to report the occurrence of some abnormal operational modes in soft-switching converters. By constructing a Boolean matrix based on the states of the switching components, some unexpected topological states are identified. Consequently, these states excite the abnormal or sneaking operational modes as referred. A three-stage step-up zero-current switching converter is used ...

Modern power converters frequently require snubberless operation of p-i-n diodes [1]. Due to the presence of fast-switching components, like last-generation GTOs and IGBTs, the diodes must be able to withstand, at turn-off, quick inductive switching, i.e., large, negative time derivatives of the diode current ((dID/dt)1<0) without large overvoltages, which requires a limited time derivative ((d...

In this paper, a multiphase boost converter is proposed to achieve high voltage gain and high power gain. The proposed converter operates in continuous conduction mode (CCM) with soft switching of main and auxiliary devices. The transformer in a conventional converter is replaced by an auxiliary circuit which provides the desired voltage and power levels. The zero voltage switching (ZVS) and ze...

This paper presents a novel three-phase utility frequency to high frequency soft switching power conversion circuit with dual mode pulse width modulation and pulse density modulation for high power induction heating applications as melting of steel and non ferrous metals, annealing of metals, surface hardening of steel and cast iron work pieces and hot water producers, steamers and super heated...

This work presents a novel highly efficient and low-stress battery charger with a resonant switch converter— based on resonance and zero-voltage-transition soft-switching theory—that reduces defects associated with high voltage and high current stresses caused by the resonance of traditional resonant circuits. The novel battery charger meets the requirement that all circuit components must oper...

A zero-voltage, zero-current switching (ZVZCS) PWM DC-DC power converter with secondary active rectifier tested as a dc current source for arc welding is described in this paper. The soft switching DC-DC converter consists of high frequency inverter, high frequency power transformer and controlled output rectifier with new secondary energy recovery turn-off snubber. Circulating current in the c...

The pulse density modulation technique has been used in resonant power converters because its ability to maintains soft-switching for any level of output power. The sub harmonics of the switching frequency are in general undesired and are seen as a drawback. In this work are developed analytical equations to express the harmonics and sub harmonics components of a PDM signal. It is still analyze...

This paper presents considerations on the switching frequency and duty cycle & operating equations of softswitching BUCK chopper. These considerations are discussed and applied to selected soft-switching families such as ZVS-QRC, ZCS-QRC, ZVS-QSW-CV, ZCS-QSWCC, ZVT-PWM and ZCT-PWM [1]. The limitations on switching frequency and duty cycle are derived in terms of: chopper input voltage (Vg), cho...

In this study, an interleaved soft switching Boost Converter is used to track the maximum power point of PV array and full bridge inverter is used to stabilize the dc bus voltage. In this method, an interleaved technique is adopted to reduce the current rating of each device. Switching losses are reduced by adapting a zero voltage transition which increases the efficiency of the system. The exp...