Development of a low cost commercial switching mode power supply

• Main Author: Gopal Narayanamurthy.
• Other Authors: Ali Iftekhar Maswood
• Format: Final Year Project
• Language: English
• Published: 2012
• Subjects: DRNTU::Engineering::Electrical and electronic engineering::Power electronics
• Online Access: http://hdl.handle.net/10356/49859
• Institution: Nanyang Technological University

The world drive towards smaller, lighter, cheaper and more efficient electronics has led to the development of switching-mode power conversion technology.A Switched-Mode Power Supply is an electronic power supply that incorporates a switching regulator in order to be highly efficient in the conversion of electrical power. Like other types of power supplies, an SMPS transfer’s power from a source like the electrical power grid to a load (e.g., a personal computer) while converting voltage and current characteristics. An SMPS is usually employed to efficiently provide a regulated output voltage, typically at a level different from the input voltage.This project presents a theoretical background, design and realization progress of a low cost single output switch mode power supply (SMPS) for commercial application that will incorporates a switching regulator in order to provide the required DC output 50V, with rating of 75W. It has a fly back topology and utilizes one power switch to facilitate the transfer of energy from the input to output. In this switched-mode power supply switches a power transistor between saturation and cutoff with a variable duty cycle whose average is the desired output voltage. It switches higher frequency 40 kHz than that of the AC line, which means that the transformer that it feeds can be much smaller than one connected directly to the line/mains. Switching creates a rectangular waveform that typically goes to the Primary of the transformer typically secondary feed rectifiers and filter capacitors to provide various DC outputs with low ripple.