| 摘要 |
<p>A controller for an AC rotary machine is proposed, by which a stable rotation angular-frequency estimate value can be obtained even in an extremely low speed region of the AC rotary machine, and consequently stable control can be performed. A controller for an AC rotary machine has an angular- frequency estimate output means (20) that outputs an angular-frequency estimate value Éi based on an angular-frequency calculated value (É1) including a rotation angular-frequency estimate value (Ée). The angular-frequency estimate output means (20) has lower-limit constant-value output means that outputs a lower-limit constant value (É2), comparison means that compares the angular-frequency calculated value É1 to the lower-limit constant value (É2), and switching means that performs switching operation according to the comparison means, wherein the switching means outputs the angular-frequency calculation value (É1) as the angular-frequency estimate value Éi when the angular-frequency calculation value (É1) is larger than the lower-limit constant value (É2), and outputs the lower-limit constant value (É2) as the angular-frequency estimate value Éi when the angular-frequency calculation value (É1) is equal to or less than the lower-limit constant value (É2).</p> |
