| 摘要 |
PURPOSE:To prevent the trip of an inverter device by actuating the inverter device so as to compensate for the deviation of the speed when the speed of a rotating work does not coincide with the speed of a rotating body driven by an inverter. CONSTITUTION:When a motor is in a regenerative condition, the DC voltage of a smoothing circuit 1 rises by the regenerative voltage. This voltage is detected by a voltage detecting means 10 and a DC voltage rise judging means 11, and when the detected value exceeds the limit value, it is outputted to a frequency command fixing means 20. The frequency command fixing means 20 selects the upper limit frequency when there is the output from the DC voltage rise judging means 11, while it selects the lower limit frequency when there is no output. This constitution increases the output frequency to discontinue the regenerative condition when the DC voltage is increased in the regenerative condition. When the DC voltage is below the limit value, the output frequency is decreased, and the load is reduced in the power running condition. That means, the deviation from the number of revolutions of a work is compensated for. |
