If you are looking for a converter from 220 VAC to power a 3-phase motor at 50 Hz, and you connect with out a converter, maybe don´t hurt you. This will be true for a squirrel-cage motor Design A,B,C, and D (torque and current increase, speed, eficiency and power factor decrease). If the motor...
Do you try to power a "normal" PC with a inverter?. So you can have a 12 VDC PC and use a automotive battery. Remove, if you want to use the PC for control, all the devices you dont need, for example, the sound card (your even can desconnect the monitor and have your PC working !)