Voltage regulator system based on a PWM AC chopper converter

Utility power quality problems like input voltage unbalance and sag conditions severely stress electronic equipment. Voltage sag forecasting is a complex issue, since it involves a large variety of random factors, such as: type of shortcircuits in the power system, location of faults, protective system performance and atmospheric discharges. Recently, the AC-AC converters have been proposed as voltage compensator. The output voltage regulation capability of these topologies can be also used for voltage feeding regulation purposes. In this paper the proposed topology is described and checked; its main advantage is that in addition to compensate voltage sags or swells by changing the duty ratio and the absence of any transformer device, it may be used as a multipurpose line dimmer.