Introduction to power electronics

Submitted by tushar pramanick on Sun, 07/27/2014 - 18:42

1.1 Introduction

In recent times, energy conservation is one of the most popular issues through the world. Lots of debates and discussions are taking place as to how to save energy. One of the best meaningful solutions to the ever increasing energy crisis is to improve energy utilization efficiency. While power electronics can be claimed to be the best for increasing energy utilization, it puts a strong contribution towards making the energy conversion from renewable energy sources easier and more efficient.

Power electronics in broader sense actually controls the flow of power to make it suitable to be used by diverse type of instruments and appliances. In a power conversion process the task is to minimize energy loss and thereby maximize the conversion efficiency. This is most important not only from economic point of view for the money lost with energy wasted but also for inherent technical difficulty faced to remove the heat so generated due to wasted energy. Besides there are cost, size, weight issues to be considered logically.

One important reason behind the market demand and consequent development in the power electronic technology is the requirement of regulated DC power supplies. Fast development and demand of computer, communication equipment, and consumer appliances require better regulated DC supply quality and often uninterruptible power supplies. So different types of rectifier topology with different control strategy have been introduced to meet the power demand and the most common problem of these topologies are harmonic pollution in utility supply.

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Power electronics in broader aspect actually controls the flow of power to make it suitable to be used by diverse type of instruments and appliances. The ability to control the flow of power is derived from using solid state switches along with their controllers.

PWM Rectifier

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Active PWM filter

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Multi-pulse rectifier

1.4.3 Multi-pulse rectifier.

Mixing single and three phase diode rectifier

1.4.2 Mixing single and three phase diode rectifier