| 摘要 |
PURPOSE:To immediately reset a motor speed to one before momentary stop by suppressing a voltage to a predetermined value when effective power is negative at the time of momentarily stopping and restarting, and increasing only its frequency. CONSTITUTION:When a power interruption occurs, an inverter 2 is stopped. When a power source is recovered, a start command is output from a start instructing circuit 6, a pattern of constant V/F is output from a frequency command generator 7 and a voltage command generator 8, and the inverter 2 initiates restarting. When the inverter 2 is restarted, the energy of a motor starts regenerating to the power source, and its effective power becomes negative. Thus, the output of a comparator is inverted, and the increase in the output of the generator 8 is stopped. When the effective power becomes positive, the output of the generator 8 is returned to the pattern of the constant V/F. |
