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In this paper, a new active snubber cell for DC‐DC boost converters is introduced for the purpose of soft switching. The introduced snubber cell ensures lossless turning‐on by zero‐voltage transition (ZVT) and turning‐off by zero‐voltage switching (ZVS) of the main switch. Besides, it enables turning‐on by ZVS and turning‐off by zero current switching (ZCS) of the main diode. None of the semiconductor power devices are subjected to extra voltage stress, and all of them operate by soft switching (SS). The converter can successfully maintain the SS even under light loads. Furthermore, the proposed converter structure is advantageous in terms of simplicity and low cost. The operating modes and theoretical analysis of the introduced converter are presented and it is validated using a prototype with a 500 W output power and at the 100 kHz switching frequency. Owing to the proposed active snubber cell, the converter efficiency is achieved as 97.2%. [ABSTRACT FROM AUTHOR]

Summary: In this paper, soft switching isolated half‐bridge converter with a new active snubber cell that uses switched capacitor for renewable energy applications is proposed. The proposed snubber cell does not consist any magnetic element so that its structure is quite simple. Furthermore, the auxiliary switches in the proposed active snubber cell are exposed to only half of the input voltage. There is no additional voltage and current stress on any semiconductor devices. All semiconductor power devices in the proposed converter are operated by soft switching. The proposed converter is analyzed thoroughly, and the theoretical analyzes are affirmed by an implementation having 300‐VDC input, 20‐VDC output, 75‐W output power, and 150‐kHz switching frequency. The overall hard switching efficiency of the converter is increased from 86.4% to 92.9% by aid of the proposed soft switching snubber cell. [ABSTRACT FROM AUTHOR]

This paper introduces a novel modular active snubber cell for isolated half-bridge converters with ease of control. The novel snubber cell can achieved soft switching for all semiconductors at the proposed converter. The switches in the converter are derived simultaneously by the normal pulse-width modulation signals. The introduced snubber cell has a quite simple structure and ease of control. In this converter, the main switches turn on with zero current switching and turn off with zero voltage switching. Besides, there is no extra voltage stresses on the power elements. The proposed half-bridge DC–DC converter is analyzed in detail and its theoretical analysis is verified with a prototype having 50 A–25 V output values at 80 kHz frequency. [ABSTRACT FROM AUTHOR]

This paper introduces a novel active snubber cell for soft switching pulse width modulation DC-DC converters. In the proposed converter, the main switch is turned on under zero voltage transition and turned off under zero voltage switching (ZVS). The auxiliary switch is turned on under zero current switching (ZCS) and turned off under zero current transition. The main diode is turned on under ZVS and turned off under ZCS. All of the other semiconductors in the converter are turned on and off with soft switching. There is no extra voltage stress on the semiconductor devices. Besides, the proposed converter has simple structure and ease of control due to common ground. The detailed theoretical analysis of the proposed converter is presented and also verified with both simulation and experimental study at 100 kHz switching frequency and 600 W output power. Furthermore, the efficiency of the proposed converter is 95.7% at nominal power. [ABSTRACT FROM AUTHOR]

In this paper, a new soft-switched zero-current transition and zerovoltage transition (ZCZVT) converter is proposed for family pulse width modulation (PWM) DC-DC converters. The proposed new converter assures the main switch turning on under zero-voltage transition and turning off under zerocurrent transition. The proposed new converter also decreases electromagnetic interference noises and operates under soft switching in a wide input voltage range. There is no additional voltage or current stress on the main devices. The proposed converter has low cost and simple control and structure. The theoretical analysis of the converter is clarified and the operating intervals are given in detail. The experimental results of the converter are obtained by a prototype with 500 W and 100 kHz. The overall efficiency of the proposed converter is 98.5% at nominal output power. [ABSTRACT FROM AUTHOR]