| 摘要 |
<p>PURPOSE:To speedily cope with a variation of load current of a motor for roll of a feed screw motor by calculating a voltage to be applied for matching a voltage consumption with a set value and inputting the resultant voltage to a PWM output calculating and controlling means when a power consumption of the motor corresponding to previously set power does not match a set value. CONSTITUTION:A prescribed PWM calculated from a revolution speed of the feed screw motor 28 corresponding to previously set electric power is inputted to the motor 28. Then, an effective current value obtained by an effective current value calculating means 6, an effective voltage value obtained by an effective voltage value calculating means 7 and a power factor obtained by a power factor calculating means 8 are inputted to an electric power calculating means 9, and the power consumption at that time point is calculated. When the calculated power consumption does not match the set value, the voltage to be applied for making the voltage consumption match the set value is calculated by an output voltage value calculating means 5 and the resultant voltage is inputted to the PWM output calculating and controlling means 2 to correct the power consumption so as to match it with the power of the electric calculating means 9.</p> |
