| 摘要 |
<P>PROBLEM TO BE SOLVED: To perform speed sensorless vector control to an induction motor. <P>SOLUTION: The speed sensorless vector control device comprises an excitation current command value operation means 21, a torque current command value operation means 22, a current control means 23, a γ-δ/three-phase coordinates transformation means 24, an integrator 25, a three-phase/γ-δ coordinates transformation means 26, a magnetic flux estimation means 27, a slip frequency & primary frequency estimation means 28, and the like for separating the primary current and voltage of the induction motor 2 to γ-axis and δ-axis components for controlling independently. By using the magnetic flux estimation means 27 and the frequency & primary frequency estimation means 28, for example, even if the primary frequency reaches or becomes closer to a zero frequency, for example when the induction motor 2 shifts from a regenerative state to a braking one; more accurate slide frequency estimation values and primary frequencies of the induction motor 2 are obtained. <P>COPYRIGHT: (C)2008,JPO&INPIT |
