| 摘要 |
PURPOSE:To rapidly control a motor to the desired target rotating speed by reversely driving the motor when the rotating speed of the motor is faster by the prescribed speed then the target rotating speed or when the target rotating speed is altered to a low speed. CONSTITUTION:When a speed voltage Vn becomes larger than the second reference voltage Vth, the output of a detector 16 becomes a low signal, and a drive circuit 15 reversely drives a motor 11. In this case, an output voltage -Vs is applied from an inverter 17 to the input terminal IN. The voltage -Vs relates to the acceleration in the reverse drive. Thus, the reverse drive force becomes larger than a brake force due to the regenerative brake at normal rotation time, the rotating speed of the motor 11 in the normal rotation is abruptly decreased to reduce the speed voltage Vn lower than the second reference voltage Vth. Then, since the output of the detector 16 is inverted, the erroneous voltage Vs of the comparator 14 is applied to the input terminal IN, and the drive circuit 15 controls the motor 11 at constant speed in the normal rotation driving state. |
