| 摘要 |
PURPOSE: To control torque in a wide speed range, by calculating and comparing the torque with a torque command after direct-axis and right-angle-axis factors of flux, along with at least two phase currents of a stator, are detected, and receiving a difference signal and tuning a current command with a slip frequency command. CONSTITUTION: When a universal magnetic field (UFO) controller is operated in a direct field adjustment mode, a field detecting means 11 measures a direct- axis (d) factor Ψ<s> d and right-angle-axis (q) factor Ψ<s> q from each phase current of a stator. A current detecting means 13 measures each phase current values i<a> s and i<b> s . The measured values of flux and current are fed to a field adjustment calculator (CFO) 12. The calculator (CFO) 12 determines an amplitude and an angle factor of flux from these measured values and generates flux amplitude square feedback Ψ<2> . In addition, the calculator (CFO) 12 determines a torque value Tem of an induction motor promptly to carry out feedback and tune a slip frequency ω<m> a * with a current command i<a> sq * for generating the torque. |
