TABLE OF CONTENTS As described in Chapter 3, all AC/AC (AC/DC/AC) converters are treated as a first-order-hold (FOH) element in digital control systems. We will discuss this model in various circuits in this Chapter.
AC/AC and/or AC/DC/AC converters are newly developed group of the power switching circuits applied in industrial applications in comparison with other power switching circuits. Although choppers were popular in AC/DC/AC power supply long time ago, power AC/DC/AC converters were used in industrial application since later 1980s. Semiconductor manufacture development brought Power devices such as gate turn-off thyristors (GTO), Triac, bipolar transistors (BT), insulated gate bipolar transistors (IGBT) and power MOS field effected transistors (MOSFET) and so on into the DC/AC power supply since 1980s. Due to the low switching frequency devices the equipment power rate is not very high.
The DC power supply equipment was totally changed since 1960s because of the thyristor (SCR) produced. The corresponding control circuit is gradually changed from analog control to digital control system since 1980s. The mathematical modeling for all AC/DC/AC converters is discussed widely in worldwide. Finally, a FOH is generally accepted to be used for simulate the AC/AC and AC/DC/AC converters.
AC/AC converters are used for converting one AC power source into another AC power application. They are generally used in following applications:
single-phase AC/AC voltage controllers;
three-phase AC/AC voltage controllers;
single-phase input single-phase output (SISO) cycloconverters;
three-phase input single-phase output (TISO) cycloconverters;
three-phase input three-phase output (TITO) cycloconverters;
AC/DC/AC pulse width modulation...
