| 摘要 |
PURPOSE:To detect net effective drive torque current content except acceleration/deceleration torque current content for accelerating/decelerating the inertia of a load containing motor itself of torque current content by providing a no load simulator circuit. CONSTITUTION:A no load simulator 29A produces the difference between the primary frequency omega0 of a motor and a motor speed omegara, i.e., multiplies the slip frequency sa by the secondary magnetic flux PHI1* by a multiplier 51 to produce the secondary slip voltage e2a and further divides it by R2 to obtain accelerating/decelerating current reference iA*. The reference iA* is multiplied by a multiplier 53 by the secondary magnetic flux PHI2* to produce accelerating torque GA, further integrates by 24 to produce motor speed omegara. Thus, since the accelerating/decelerating current reference iA* is calculated, this is subtracted from the torque current reference i1q* of the motor, thereby obtaining the effective load current iR. |
