INTRODUCTION:
Power electronic circuits that convert a dc voltage to difference dc voltage level are known as the DC-DC converters. It uses semiconductor devices to perform its operations by controlling or modifying a voltage current. There are different types of conversion method such as electronic, linear, switched-mode, and so on. Whenever we want to change DC electrical power from one level to another level, switched-mode DC-DC converter has been chosen because is much efficient due to the reduced losses in the electronic switch. Switched-mode DC-DC converters is also known as switching power supplies or switchers.
The DC-DC converter can be divided into two categories; Isolated DC-DC converter and Non-isolated DC-DC converter. ‘Isolated’ means there are electrical barrier between the input and output of DC-DC converter such as transformer. This transformer provides electrical isolation between input and output more efficiency. For non-isolated DC-DC converter, there are no electrical barrier between input and output and its make this converter to be smaller and less expensive.
In this project, we will reviews the various types of isolated DC-DC converters. This review is categorized by converter types, mode of operation, simulation, applications and ratings of the converters. For every section, it will be address on the advantages and disadvantages of converters as well as the comparison. At the end of the paper, the conclusion will be drawn.
TYPES OF ISOLATED DC-DC CONVERTERS:
There are various types of isolated DC-DC converters which are flyback converter, forward converter, full-bridge converter and push-pull converter. Basically, isolated DC-DC converter can be used to step-up or step-down voltages and currents in the...
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...ings. This made copper losses becomes lower.
At secondary winding, the ripple is too low compared to flyback converter. This resulting that output inductor and flywheel diode remain constant in the output load.
The energy stored in inductor is available to the load. This made size of capacitor quite small and can reduce the output ripple voltage. Furthermore, the rating for ripple current for this capacitor will be much lower than required in flyback converter.
Due to high inductance of primary winding of the transformer, the power transistor has a lower peak current.
The output ripple voltage is lower.
More energy efficient compared to other isolated converter.
DISADVANTAGES:
Higher cost because of the extra output inductor and freewheeling diode.
For discontinuous current mode, the excessive output voltages will produce.
The inductor is typically larger.
Muller, S., Prowse, D. L., & Soper, M. E. (2012, September 25). CompTIA A+ Cert Guide: Power Supplies and System Cooling | Foundation Topics | Pearson IT Certification. Retrieved March 20, 2014, from http://www.pearsonitcertification.com/articles/article.aspx?p=1945640
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