Patent ID: 7298105

Claim:
A motor drive system, comprising: a switching system including a plurality of switching devices coupled between a power source and a motor and operative according to a corresponding plurality of switch control signals; and a motor startup control system for controlling the motor speed during startup, the motor startup control system comprising: a hybrid model reference adaptive system (MRAS) component including: a torque-based MRAS component providing a first error term at least partially according to a calculated torque value and an estimated torque value; and a rotor flux-based MRAS component providing a second error term at least partially according to a calculated rotor flux and an estimated rotor flux; a speed estimate controller providing a rotor speed estimate according to a controller error input; a motor controller providing a motor controller output for controlling the motor speed during startup according to a desired startup speed profile and according to the rotor speed estimate; a switch control circuit providing the switch control signals to the switching system during startup of the motor according to the controller output; and an error selector operatively coupled with the hybrid MRAS component and with the speed estimate controller to provide the error input to the speed estimate controller, the error selector providing the first error term as the controller error input when the rotor speed estimate is in a first speed range and providing the second error term as the controller error input when the rotor speed estimate is in a second speed range.