Patent ID: 8242721

Claim:
A position-sensorless control system for an electric motor having a stator and rotor comprising: an inverter for providing power to the electric motor; and a controller for controlling said inverter by transmission of control commands for operation of the motor, said controller comprising: a sensorless block for estimating an estimated rotor angular position and an estimated rotor angular velocity, wherein the sensorless block generates an estimated rotor angular position feedback signal and an estimated rotor angular velocity feedback signal; an estimated angle error detector block for detecting the difference between the estimated rotor angular position and a real rotor angular position, said detected difference being used by the sensorless block to estimate the estimated rotor angular position; a field-weakening block which receives the estimated rotor angular velocity feedback signal generated by the sensorless block to command direct axis current and generate a torque feedback signal; and a torque-to-current converter block which receives the torque feedback signal generated by the field-weakening block and derives a torque current component for the motor control command; wherein said estimated rotor angular position feedback signal is also used to generate the motor control command.