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International Research Journal of Engineering and Technology (IRJET)

e-ISSN: 2395-0056

Volume: 11 Issue: 11 | Nov 2024

p-ISSN: 2395-0072

www.irjet.net

Analysis of a Buck-Boost Converter Shruti Das1, Sukesh Sahu2 , Ganesh Ram Ratnakar3, Mohini Moitra Bhaduri4, Vikas Chandra5 1, 2

- BTECH Scholar, Chouksey Engineering College, Bilaspur

3, 4, 5

– Assistant Professor, Chouksey Engineering College, BilaspurDepartment of Electrical & Electronics Engineering ------------------------------------------------------------------------------***--------------------------------------------------------------------------------

Abstract

This paper proposes a DC-DC buck-boost converter designed to achieve a lower output voltage than the input voltage while maintaining high efficiency. The converter utilizes a topology similar to a conventional buck converter, employing a MOSFET switch, paired inductors, a switched capacitor, diodes, and a load resistor. This configuration allows for the generation of a negative output voltage with a low duty cycle, resulting in high voltage gain.

Stage I: Switch On Mode (Figure 2(b)): When the MOSFET switch (S) is turned on, diodes D1 and D2 are reverse-biased and thus off. The input voltage (Vin) supplies current through inductor L1, storing energy. Simultaneously, capacitor CL discharges, providing current to the load resistor (RL).

Key Words: DC-DC buck converter, DC-DC buck boost converter, efficiency, voltage gain, duty cycle

1. INTRODUCTION

L2 CL

DC-DC converters are essential components in modern electronic systems, enabling the efficient transfer of DC power between different voltage levels. Buck converters are commonly used for stepping down voltages, while buck-boost converters offer the flexibility of both step-up and step-down operation. However, traditional buck- boost converters often suffer from lower efficiency compared to buck converters. This paper addresses this limitation by proposing a buck-boost converter topology based on the buck converter structure to achieve higher efficiency while achieving negative output voltage with high voltage gain.

2. OPERATION AND STEADY-STATE ANALYSIS

Fig. - 2(b) Circuit configuration of switch on mode of proposedbuck boost converter Stage II: Switch Off Mode (Figure 2(c)): When theswitch is turned off, diode D1 becomes forward- biased and conducts, while diode D2 remains off. Inductor L1 now discharges, providing current through diode D1 and capacitor CL, which continues to supply the load.

The proposed converter’s circuit configuration is shown in Figure 2(a). It comprises a DC input voltage (Vin), a MOSFET switch (S), paired inductors (L1 & L2), diodes (D1 & D2), a capacitor (CL), and a load resistor (RL). The operation can be divided into two stages: Fig. - 2(c) Circuit configuration of switch off mode of proposed DC-DC buck boost converter The steady-state operation can be analyzed by applying voltage-second balance to the inductor L1. During the ontime (DT), the voltage across L1 is (Vin - 2Vout). During the off-time ((1-D)T), the voltage across L1 is Vout. Equating the volt- seconds yields:

Fig.-2(a) Circuit configuration of proposed DC-DC buck boostconverter

Impact Factor value: 8.315

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