| 摘要 |
PURPOSE: To adjust torque for a desired value in the maximum voltage and in the vicinity of the maximum voltage at all frequencies by determining the difference between the reference value and the actual value of the angle between the stator magnetic flux and the rotor magnetic flux on the basis of the value representing the torque change requirement of an electric motor. CONSTITUTION: Torque is controlled by using the angle between the stator magnetic flux and the rotor magnetic flux. The rotor magnetic flux is nearly constant for a short time at rotor co-ordinates, and a high speed torque change can be made by the high speed change of the angle (r) between the stator magnetic flux and the rotor magnetic flux. The angle change Δr is made by phase- shifting the stator magnetic flux with respect to the correct value. The angle change Δr is made by changing the limitation of magnetic flux sectors θ=0, θ=1, θ=2... with respect to the angel Δϕ. The angle Δϕ can be computed on the basis of Δr and past information. |
