| 摘要 |
PURPOSE:To enable to automatically set the optimum field current value in the state that a motor is installed on an electric automobile by gradually varying the field currents of motors, respectively, and using as the optimum field current value the field current value when the peak values of the armature currents of the respective motors coincide. CONSTITUTION:When a transistor TR is turned ON or OFF, the armature currents IA1, IA2 respectively flowed through armatures A1, A2 become sawtooth waveform. At this time, any one of the field currents IF1, IF2 respectively flowed through field coils VC1, VC2 is fixed, and the other is gradually altered. The field currents IF1 and IF2 when the peak values IAP1, IAP2 of the currents IA1, IA2 are stored as the optimum field current value, and the field currents are thereafter controlled on the basis of the thus stored field current value. |
