Soft start system for motors utilizing variable frequency drive and autotransformer

A soft start system for starting large motors has a power supply suitable for passing power to the motor, a variable frequency drive connected to the power supply and an autotransformer connected between the variable frequency drive and the motor for passing power of an elevated current to the motor. A switch is connected between the motor and power supply for connecting the motor to the power supply when the motor reaches a desired speed. The autotransformer includes a single core with a winding extending over the single core. The autotransformer includes a first terminal connected the variable frequency drive, a second terminal connected the motor and a grounded neutral.