| 摘要 |
PROBLEM TO BE SOLVED: To sustain the essential control properties of vector control by estimating primary and secondary resistance containing no differentiation term even under conditions of constant rotation or constant torque operation. SOLUTION: A secondary resistance estimating means 11 estimates a secondary resistance R2 from voltage values vu*, vv*, vw* and current values iu, iv, iw to an induction motor 8, the frequency ωm thereof, currently set primary inductance, secondary inductance, mutual inductance, slip angular frequency ωs, and primary resistance R1 according to a formula applicable even to constant rotation or constant torque operation. A primary resistance estimating means 12 operates a primary resistance regardless of the secondary resistance and slip angular frequency and updates a set value. |
