Driving method and system for electrical rotating machine having two rotors using compound current

In driving method and system for an electrical rotating machine, the electrical rotating machine comprising two rotors, each rotor being independently driven by means of a compound current generated by a multi-phase inverter, and a stator on which a plurality of stator coils are wound, the respective stator coils are divided into a plurality of groups thereof, a total current sum of each group thereof being zeroed and neutral points of the stators belonging to the respective groups being interconnected and drive pulses are supplied to a plurality of inverter arms of the inverter associated with one group of the stator coils independently of those supplied to other inverter arms of the inverter associated with the other group of the stator coils.