| 摘要 |
PURPOSE: To reduce a peak current to a minimum at the rise of torque and lower a current promptly at the fall of torque, by optimizing a cut-off frequency for a target-torque transfer function and a target magnetic-flux transfer function in a changing direction of the target torque. CONSTITUTION: A stationary loss minimum flux calculating unit 11, a target flux calculating unit 12, a target torque calculating unit 14, a target torque change detecting unit 18, and a cut-off frequency setting unit 19 are provided in addition to conventional vector control units 13, and 15 to 17. In a control system, torque responsibility and flux responsibility are changeable independently. The cut-off frequency (ωγ ) of a target torque transfer function and a cut-off frequency (ωϕ ) of a target flux transfer function are adequately optimized in a changing direction of the target torque (Tm ). Then, a loss in transient time is optimized under control, and a peak current at the rise of torque is reduced to a minimum and a torque current or induction current is reduced promptly at the fall of torque. |
