| 摘要 |
PURPOSE: To prevent the decrease of accelerating torque at high-speed without lowering starting torque by deciding the phase difference between AC voltage and AC current flowing in an armature coil so as to be a specified value or less, preferably zero. CONSTITUTION: An angle-of-rotation detecting means 7 detects each speed on an engine 1 and the positions of the magnetic poles of a synchronous machine 2, and transmits them to a controller 5. In the ROM of the controller 5, the three-dimensional map of a phase angle with AC current I and field current If is stored beforehand, and a search is made by putting I and If in. Next, the phase angle θof V to E is determined by tanθ=ωLI/(V-R1). Next, the field current If is increased when large torque is required, and the field current If is decreased when the torque is required to be decreased. Namely torque is adjusted by controlling If . Consequently, it is possible to have comparatively large counterelectromotive force E relating to the mechanical output of the motor even at high-speed time, and to prevent the decrease of high-speed time accelerating torque without lowering starting torque. |
