| 摘要 |
PURPOSE:To shorten acceleration/deceleration time of motor by providing a plurality of frequency division point setting means, a plurality of frequency increasing rate setting means and frequency decreasing rate setting means, and a frequency increasing/ decreasing rate selecting means thereby utilizing output torque effectively when an inverter and an AC motor are used in combination. CONSTITUTION:An acceleration/deceleration operating unit 5 receives an acceleration time set value, a deceleration time set value and frequency division points and operates frequency increase rate and decrease rate, respectively, for a plurality of frequency sections divided at the frequency division points and then set values for frequency increase rate setter and frequency decrease rate setter are determined based on the operation results. An acceleration/deceleration switching commander 9 receives a frequency set value from a frequency setter, a set value from a frequency division point setter and an output frequency and makes a judgment whether the frequency is increasing or decreasing or the variation thereof is zero and further makes a judgment in which frequency section the frequency is increasing or decreasing. Commands are then provided, based on the judgment results, to an increase rate switch 11, a decrease rate switch 13 and acceleration/deceleration switches 12, 21, 24. |
