I made a 1 phase to 3 phase inverter using arduino and IR2104 to control the speed of an induction motor and it is working perfectly.
To complete the protection scheme, I need to monitor voltage of each phase to protect motor if one phase is lost due to malfunction of IGBT or something else.
In addition, I need to monitor current for overcurrent protection.
In case of voltage I know that it is possible to use optocoupler to convert high level voltage to logic level 5 VDC. Is there any better and simpler practical method to monitor voltage and current of each phase for such application?!