| 摘要 |
<p>PURPOSE:To obtain high magnetic flux calculating accuracy by storing a correcting signal immediately before the correcting operation is stopped in a low speed range or light load range, and continuously correcting a current model calculating magnetic flux subsequently with the correcting signal. CONSTITUTION:When the secondary time constant of a current model magnetic flux calculator 20 is corrected by the output of a voltage model magnetic flux calculator 24, the secondary time constant correcting circut 101 detects a low speed range or a light load range that the correcting operation becomes impossible from a torque current target value iT* rotating speed (n). The correcting signal immediately before the correcting operation is stopped is stored, and the current model calculating magnetic flux is continuously corrected subsequently by the memory signal. Thus, even in low speed range and light load range, the magnetic flux correction is enabled to resultantly obtain high magnetic flux calculating accuracy similar to the high speed and heavy load ranges.</p> |
