| 摘要 |
PURPOSE:To perform stable current control by setting a gain changing means for computing the arithmetic parameter of a PWM processing means to be changed, from the PWM width of the computed result of the PWM processing means. CONSTITUTION:A motor 11, an inverter circuit 12 consisting of a DC power source and four transistors, a current detector 13 for detecting current flowing to the motor 11 and converting the current to voltage, a micro-computer 15, and the like are arranged. The micro-computer 15 is provided with a current command processing means for computing a current command value, a PWM processing means for computing the width of PWM signal, and a gain changing means for computing the arithmetic parameter of the PWM processing means to be changed, from the time width of the PWM signal of the computed result of the PWM processing means. Besides, by a PWM circuit 16, a PWM width obtained through the micro-computer 15 is changed to the PWM signal, and the output is directed to the inverter circuit 12. When the PWM width is large, then a gain is lowered, and when the PWM width is small, then the gain is heightened. As a result. the oscillation of current is suppressed and can stably be controlled. |
