| 摘要 |
PURPOSE:To stably operate an inverter irrespective of the variation in the voltage of a power source by automatically regulating the switching point of correcting the voltage and correcting the frequency in response to the voltage of the power source. CONSTITUTION:An inverter output frequency and voltage command is inputted to a voltage control amplifier 1 and a V/F converter 2. The output of the amplifier 1 is used as an inverter output voltage command, and the output of the converter 2 is used as an inverter output frequency command. The voltage command and the frequency command are corrected in proportion to the variation in the load current by a correcting circuit which has differentiators 4, 5 a control range discriminator 6, a driver 7, a power source voltage detector 8, a voltage difference detector 9 and an inverting amplifier 10, and the correcting switching point is automatically regulated in response to the voltage of the power source. |
