| 摘要 |
PURPOSE:To prevent irregular operation without generating reverse torque by exciting by DC a motor by exciting current phase immediately before generating a stop command. CONSTITUTION:The fact that a speed detection value fm becomes 1% of lower of rated value is discriminated by a stop command generator 7 to output a stop command. When a stop command is generated, pulses transmitted to a sinusoidal wave generator 12 and a cosine wave generator 13 are interrupted by an AND circuit 11, the output of a counter 31 is fixed, and the peak values of the sinusoidal wave Y and the cosine wave X are held. The outputs of multipliers 17, 18 are continuously maintained at the value immediately before the stop command is generated. Thus, the primary current value command becomes the magnitude and phase of the exciting current immediately before generating the stop command, and a current value feedback system 110 flows a DC current corresponding to the primary current value command. |
