A New Low-Stress Boost Converter with Soft-Switching and Using Coupled-Inductor Active Auxiliary Circuit

kground and Objectives: Many applications use boost converters as front-end circuits, including power factor correction (PFC), solar power generation, fuel cell power conversion, battery chargers, and uninterruptible power supply. In addition, boost converters have a simple structure with low component counts, which makes them a convenient choice.Methods: This article proposes a coupled-inductor active auxiliary circuit to create a new low-stress boost converter with soft-switching. The proposed auxiliary circuit supplies the main switch and diode with soft-switching ZVC turn-on and ZCS turn-off states. The main switch and diode are not deal with any extra stress of voltage or current. Furthermore, the soft switching condition is also provided for auxiliary circuit components.Results: The proposed auxiliary circuit also has a simple structure, low circulating current losses, low cost, and simplicity in control. The operation state and performance of the proposed soft-switching boost converter are examined, and the design procedure is presented. Finally, a ۲۰۰W prototype is implemented and tested to validate the theoretical results. The offered experimental data verified the theoretical analysis.Conclusion: This paper provides a new low-stress soft-switching boost converter using a simple coupled-inductor in the auxiliary circuit. Moreover, the auxiliary part consists of two diodes, one switch, one resonance capacitor, and a coupled inductor. The suggested auxiliary circuit provides soft switching condition for the main switch, which provides ZVS in the turn-on transient and ZCS in the turn-off transient, while in this situation, the soft-switching condition is provided for the auxiliary switch, which turns on under ZCS and also turns off with practically ZVS conditions. The auxiliary circuit does not impose additional voltage or current stress on the main switch. A ۲۰۰ W prototype is implemented to validate the performance of this snubber cell. The experimental data reported here support the theoretical analysis. The best point of efficiency is ۹۵.۹% which is occurred at maximum load, and is ۶.۳% greater than the traditional counterparts.

Keywords:

Boost converter , ZVS soft-switching , DC/DC Converter , PWM Converter