| 摘要 |
PURPOSE:To obtain the high responsibility and stability of torque by calculating the current phase from the detected value when the difference between the primary current command and the detected value and by adjusting the current phase to the change in size of the actual current. CONSTITUTION:Usually a phase angle switching selector 21 selects the output thetaof an inverse tangent function machine 13, but when the deviation DELTAI of the primary current detected value I1 from the primary current command value I1* is more than the comparison level, the current phase angle theta is selected by conversion with an inverse cosine function machine 19 from the primary current detected value I1 and exciting command value I m*. In the inverse cosine function machine 19 the current phase is smoothly changed, adjusting to the actual current size. On this account, the exciting current I m is almost constant and the flux phi of a motor 5 is also almost constant, so that the torque changes smoothly. |
