| 摘要 |
PURPOSE:To obtain an economical uninterruptible VVVF inverter system having high reliability by connecting a storage battery to the DC input terminal of a general-purpose inverter through a switching unit at the time of power interruption, and connecting a control power supply UPS between a normal DC power source and a control AC input terminal of the inverter. CONSTITUTION:Power is normally supplied from a normal AC power source 17, converted to a DC by a diode 51 in a VVVF inverter 5, smoothed by a capacitor 57, a variable voltage variable frequency AC power is generated by a transistor 53, and supplied to a motor 7. A charger 1 supplies a DC power adapted for charging a storage battery 3 to always charge the battery 3. When the power source 17 is interruppted, power interruption is detected by a power interruption detector 19, a thyristor used as a switch 11 is closed, and a DC power is supplied to a DC circuit of the inverter 5. Stable power of commercial power source frequency is continuously supplied even at the time of power interruption to a VVVF controller 55 through a UPS. |
