| 摘要 |
PURPOSE:To eliminate an abnormal current at a starting time by starting the operation of a variable limiter voltage circuit by an inverter operation command when the inverter is started by the minimum frequency, and applying the limiter voltage of the circuit to a correction instructing circuit. CONSTITUTION:When an inverter operation command is applied to a terminal 19, normal-close switches 20, 33 are opened, and an operational amplifier 30 of a variable limiter voltage circuit 11a starts integrating. The limiting potential of an operational amplifier 18 is restricted by the output of the amplifier 30, and the output of the amplifier 18 is linearly raised. The output of the amplifier 18 is inverted by an operational amplifier 9a, and its output is fed back to the output side of an operational amplifier 12. When this feedback voltage becomes the Zener voltage of a Zener diode 13, the output becomes constant. |
