| 摘要 |
PROBLEM TO BE SOLVED: To improve the stability and responsibility in control independently of an operation region of an electric motor.SOLUTION: A control device 10 for a three-phase AC induction motor 1 comprises a correction value calculation unit 20 calculating a slip angular frequency ωso that a rotor magnetic flux directs to a γ-axis direction, and outputting its correction value to a slip angular frequency controller 19. The correction value calculation unit 20 has: a first estimation unit for estimating a rotor resistance value on the basis of the rotor magnetic flux &phgr;of a δ-axis component, and outputting a correction value on the basis of the estimation result; a second estimation unit for estimating a rotor resistance value Ron the basis of a stator temperature Ts, and outputting a correction value on the basis of the estimation result; a control flag setting unit for determining a state of a motor torque; and a correction value output unit for outputting the correction value by the first estimation unit to the slip angular frequency controller 19 in a case where the state of the motor torque is a non-low torque state, and outputting the correction value by the second estimation unit to the slip angular frequency controller 19 in a case where the state of the motor torque is a low torque state. |
