Abstract: An integrated motor drive system includes a variable speed electric motor, a fan connected to the electric motor to generate an air flow as the motor rotates, and a motor drive connected to the electric motor, the drive including a heat sink disposed between the motor and the drive and having a plurality of asymmetrically spaced apart heat transfer fins transferring heat generated by power components in the drive to the air flow. The fan is connected to a one of either the rotor of the variable speed motor or to an auxiliary fan motor controlled independently of the variable speed motor. A fan shroud on one end of the motor acts as an air duct member adapted for dividing and directing the flow of air from the fan to sets of heat transfer fins on the heat sink. A method of operating the drive integrated type motor system includes generating motor speed command signals in the drive based on inputs from an operator through an operator interaface unit on the drive.