Patent ID: 7855901

Claim:
An AC voltage output apparatus, comprising: a first poly-phase AC electric motor including a star-connected first poly-phase winding as a stator winding; a second poly-phase AC electric motor including a star-connected second poly-phase winding as a stator winding; first and second inverters respectively connected to said first and second poly-phase windings; inverter control means for controlling said first and second inverters; and AC command voltage generating means for generating an AC command voltage for generating an AC voltage across a first neutral point of said first poly-phase winding and a second neutral point of said second poly-phase winding; wherein said AC command voltage generating means includes distributing means for distributing said AC command voltage to first and second AC command voltages based on a voltage burden ratio indicating ratio of voltage burdens to be borne by the first and second inverters for generating said AC voltage; and said inverter control means controls said first inverter based on a command voltage obtained by superposing said first AC command voltage on a command voltage of each phase for said first poly-phase AC electric motor, and controls said second inverter based on a command voltage obtained by superposing said second AC command voltage on a command voltage of each phase for said second poly-phase AC electric motor.