| 摘要 |
PURPOSE:To stably perform vector control of an induction motor following the variation of the motor constant of the motor. CONSTITUTION:A comparator 11 compares the output value of a subtractor 30 which is obtained by subtracting a torque current ideltaS from a torque current command ideltaS* with a reference value. Another comparator 12 compares the time differential value of a torque command Te* outputted from a differentiation circuit 16 with a reference value. The output of each comparator makes a weaker field computing element 15 active when (ideltaS*-ideltaS) is larger than the reference value and the differential value of the command Te* is smaller than the reference value through a gate 13 and the magnitude phiW of a weaker field is outputted based on the (ideltaS*-ideltaS). Then a magnetic flux command phigammar* becomes phigammar* comp, because phiW is subtracted from the phigammar* at a subtractor 33. The phigammar* comp is used for vector control as a new corrected magnetic flux command after passing the phigammar* comp through an LPF 14. |
