Smooth-Transition Simple Digital PWM Modulator for Four-Switch Buck-Boost Converters

This paper proposes a simple, hardware-efficient digital pulse width modulator for a 4SBB that enables operation in Buck, Boost, and Buck+Boost modes, achieving smooth transitions between the different modes. The proposed modulator is simulated using Simulink and experimentally demonstrated using a 500 W 4SBB converter with 24 V input voltage and 12–36 V output voltage range.

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Analysis of loss distribution of Conventional Boost, Z-source and Y-source Converters for wide power and voltage range

Transactions on Environment and Electrical Engineering ◽

10.22149/teee.v2i1.68 ◽

2017 ◽

Vol 2 (1) ◽

pp. 1 ◽

Cited By ~ 5

Author(s):

Brwene Salah Gadalla ◽

Erik Schaltz ◽

Yam Siwakoti ◽

Frede Blaabjerg

Keyword(s):

Output Voltage ◽

Input Voltage ◽

Industrial Applications ◽

Point Of View ◽

Small Range ◽

Voltage Gain ◽

Boost Converters ◽

Voltage Range ◽

High Voltage Gain ◽

Simulation Results

Boost converters are needed in many applications which require the output voltage to be higher than the input voltage. Recently, boost type converters have been applied for industrial applications, and hence it has become an interesting topic of research. Many researchers proposed different impedance source converters with their unique advantages as having a high voltage gain in a small range of duty cycle ratio. However, the thermal behaviour of the semiconductor devices and passive elements in the impedance source converter is an important issue from a reliability point of view and it has not been investigated yet. Therefore, this paper presents a comparison between the conventional boost, the Z-source, and the Y-source converters based on a thermal evaluation of the semiconductors. In addition, the three topologies are also compared with respect to their efficiency. In this study the results show that the boost converter has higher efficiency than the Zsource and Y-source converter for these specific voltage gain of 2 and 4. The operational principle, mathematical derivations, simulation results and final comparisons are presented in this paper.

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Hybrid DC-DC Converter with Low Switching Loss, Low Primary Current and Wide Voltage Operation

Energies ◽

10.3390/en14092536 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2536

Author(s):

Bor-Ren Lin ◽

Yi-Kuan Lin

Keyword(s):

Pulse Width ◽

Pulse Width Modulation ◽

Input Voltage ◽

Resonant Circuit ◽

Switching Loss ◽

Voltage Range ◽

Current Loss ◽

Zero Voltage Switching ◽

Energy Applications ◽

Multi Stage

A full-bridge converter with an additional resonant circuit and variable secondary turns is presented and achieved to have soft-switching operation on active devices, wide voltage input operation and low freewheeling current loss. The resonant tank is linked to the lagging-leg of the full bridge pulse-width modulation converter to realize zero-voltage switching (ZVS) characteristic on the power switches. Therefore, the wide ZVS operation can be accomplished in the presented circuit over the whole input voltage range and output load. To overcome the wide voltage variation on renewable energy applications such as DC wind power and solar power conversion, two winding sets are used on the output-side of the proposed converter to obtain the different voltage gains. Therefore, the wide voltage input from 90 to 450 V (Vin,max = 5Vin,min) is implemented in the presented circuit. To further improve the freewheeling current loss issue in the conventional phase-shift pulse-width modulation converter, an auxiliary DC voltage generated from the resonant circuit is adopted to reduce this freewheeling current loss. Compared to the multi-stage DC converters with wide input voltage range operation, the proposed circuit has a low freewheeling current loss, low switching loss and a simple control algorithm. The studied circuit is tested and the experimental results are demonstrated to testify the performance of the resented circuit.

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