Voltage sags and extended undervoltages are one of the main concerns of industry today. These voltage sags could cause high negative impact on productivity, which is certainly an undesirable aspect in industrial and commercial applications. Current tap-changing transformers used in distribution systems have proven to be inadequate in solving these problems related to line regulation. A solution to these problems is to install an AC voltage-voltage converter that has been developed primarily for voltage-sag correction. This system incorporates high-speed insulated gate bipolar transistor switching technology and was designed to provide the speed and efficiency required by industrial customers. Furthermore, the system will provide the flexibility of installation with or without the incorporation of tap-changing transformers. Simulation results show the operations involved in voltage-sag correction of the AC voltage-voltage converter. A single-phase system can be readily developed into a three-phase converter system based on the exact principle of operation.