| 摘要 |
PURPOSE:To supply a stable power source by controlling the pulse width of an inverter at a high speed to suppress a voltage variation when detecting the variation, and returning to the prescribed value having less high frequency components to shift to a normal control when approaching to the normal state. CONSTITUTION:A DC power source 1 is stepped down by a chopper 2, and supplied through a DC reactor 3 and a capacitor 4 to an inverter 5. It is converted by the inverter 5 to an AC of the prescribed frequency, and supplied through a transformer 6 and a filter 7 to a load 8. This controller has a chopper driver 21, a constant voltage controller 23, a voltage variation suppressor 54, a pulse width variation amount reducing circuit 55, and further has a detector 84 for detecting when a deviation is large, a high speed process switch 85, and low speed process switches 86, 87. Thus, when the voltage variation is large, the pulse width of the inverter 5 is controlled to suppress the voltage variation, and when shifted to the normal control, it is shifted by the pulse having less harmonic components. |
