Patent ID: 6448735
Filing Date: 2002-09-10
Classification: H02P

Abstract:
A method for controlling the torque and power factor of a doubly fed machine using direct torque control, comprising the steps of:(a) calculating the estimated torque of said machine; (b) determining a torque error from said estimated torque and a reference torque; (c) calculating the desired rotor flux command &PSgr;r_ref; (d) calculating the actual rotor flux &PSgr;r; (e) converting said actual rotor flux from the stator reference frame to the rotor reference frame by multiplying &PSgr;r by eâˆ’j&thgr;m; (f) determining a flux error from said desired rotor flux command and said actual rotor flux converted to the rotor reference frame; and (g) selecting an inverter voltage vector from said torque error and said flux error.