FIELD: adjustable-frequency ac drives using squirrelcage and slip-ring induction motors, three-phase voltage regulators, and synchronous condensers with booster transformers. SUBSTANCE: ac voltage converter used for converting voltage variables (amplitude, phase, and frequency) is capable of controlling all three variables of ac voltage and also it is capable of regulating only two variables (amplitude and frequency and/or amplitude and phase). Converter has three- phase inverter with frequency and/or phase control system and reversible rectifier with isolated amplitude control system. Reversible rectifier has three-phase controlled rectifier and three-phase driven-circuit inverter. These three devices incorporated in power circuit of converter are provided with interrelated dc terminals and isolated ac terminals. EFFECT: enlarged functional capabilities and fields of application. 2 dwg
