| 摘要 |
PURPOSE:To reduce the capacity of a power source side converter by increasing a control leading angle only in the transient state for increasing a current to lower the power factor, and reducing the voltage of a DC middle circuit. CONSTITUTION:After a voltage from a power source is converted by a power reactor 1 to a DC, the DC is again converted to an AC by an inverter 2, and supplied to a motor 3. A current of a DC middle circuit is detected by a detector DE, applied to a current regulator 6, and the regulator 6 controls the firing of the reactor 1 through a firing angle regulator 7. A differentiator 8 produces a change rate of a current command value, i.e., an output proportional to the voltage applied to a reactor 4, subtracts the output by the prescribed value, and then applies to a commutation margin angle calculator 10. After the output of the calculator 10 is limited by a controller 12, it is applied to a control leading angle calculator 13 to generate a gate pulse for the inverter 2 from the calculator 13. |
