From Fundamentals of Power Electronics, Second Edition

1.1 INTRODUCTION TO POWER PROCESSING

The field of power electronics is concerned with the processing of electrical power using electronic devices [1 7]. The key element is the switching converter, illustrated in Fig. 1.1. In general, a switching converter contains power input and control input ports, and a power output port. The raw input power is processed as specified by the control input, yielding the conditioned output power. One of several basic functions can be performed [2]. In a dc-dc converter, the dc input voltage is converted to a dc output voltage having a larger or smaller magnitude, possibly with opposite polarity or with isolation of the input and output ground references. In an ac-dc rectifier, an ac input voltage is rectified, producing a dc output voltage. The dc output voltage and/or ac input current waveform may be controlled. The inverse process, dc-ac inversion, involves transforming a dc input voltage into an ac output voltage of controllable magnitude and frequency. Ac-ac cycloconversion involves converting an ac input voltage to a given ac output voltage of controllable magnitude and frequency.


Figure 1.1: The switching converter, a bask power processing block.

Control is invariably required. It is nearly always desired to produce a well-regulated output voltage, in the presence of variations in the input voltage and load current. As illustrated in Fig. 1.2, a controller block is an integral part of any power processing system.


Figure 1.2: A controller is generally required.

High efficiency is essential in any...

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Products & Services
Switching Power Supplies
Switching power supplies are DC sources that use a switching element (normally a power transistor) to generate the desired voltage. Switching power supplies are also called switch-mode products or switching mode power supplies (SMPS).
DC Power Supplies
DC power supplies accept an input power and output the desired form of DC power. Common types of DC power supplies include linear power supplies, switching power supplies, DC-DC converters, and silicon controlled rectifier (SCR) type power supplies.
Frequency-to-Current Converters
Frequency-to-current converters accept a frequency (an AC signal) and produce an output current whose value is a function of the input frequency.
Power Supplies
Power supplies are electrical devices that deliver electric power to one or several loads. They generate the output power by converting an input signal into an output signal.
AC-DC Converter Chips
AC to DC converter chips transfer an AC input into DC power using switching (MOSFET, IGBT) or rectification (diodes, Schottky diodes).

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