| 摘要 |
PURPOSE:To be hardly restricted by operational commutating conditions in a wide range by changing an output voltage phase difference between respective banks according to running frequency. CONSTITUTION:A commercial AC power source 1 is connected to an induction motor 5 via two-line banks consisting of two-line power rectifiers 2A, 2B, and power inverters 4A, 4B. A speed reference N* set by a speed setting device 11 is used as frequency reference f* and is also used as motor voltage reference V*. Motor voltage is controlled by the power rectifiers 2A, 2B via a voltage regulator 14 and current regulators 19A, 19B, and frequency is controlled by the power inverters 4A, 4B via ignition controlling circuits 21A, 21B. By a circuit 16 for controlling a phase difference between the banks, according to the frequency reference f*, the phase difference between the banks is determined, and is applied to the ignition controlling circuits 21A, 21B. |
