| 摘要 |
PURPOSE:To compensate the decrease in the voltage of a power source due to the variation in a load by connecting a motor in series with a transistor, and detecting the input and output side voltage of an armature and the output side voltage of the transistor, thereby controlling a base current. CONSTITUTION:A DC motor M and a transistor Tr are connected in series with each other, and the motor M is controlled at a constant speed by controlling the base current of the transistor Tr. At this time, the input and output side voltages Vd, VB of the armature of the motor M and the output side voltage VC of the transistor Tr are respectively detected, thereby controlling the base current of the transistor Tr and decreasing the voltage VB in the amount corresponding to the voltage drop due to the resistance of a transformer T at the load time by utilizing the voltage drop of the Vd. Accordingly, the current of the motor M can be performed without influence of the voltage drop of the power source, and the voltage drop of the power source caused from the result of the reduction in size of the power transformer T can be effectively compensated. |
