ATO single phase VFDs will accept 220V single phase input and give you a 220V 3 phase output. They use what is called a "voltage doubler" front-end rectifier, meaning they rectify the AC220~240V to AC 0~input voltage, then the inverter section uses PWM to recreates an output that MOTORS react to as if it is 220VAC 3 phase. The key point however is MOTORS; this can ONLY be used for 3 phase AC induction motors, you cannot use the output as a general 3 phase power supply source. it is the inductive nature of the motor that allows the PWM to become a pseudo-sine wave. Without the motor, it's just pulsating DC that changes direction.