| 摘要 |
PURPOSE:To reduce the capacity of an AC voltage source by using plural AC voltage sources with sequential switching to reduce the maximum level of the current flowing to the primary side. CONSTITUTION:When a charge command 101 is delivered, the output 201 of a voltage detecting circuit 71 is turned on. Thus a switch 12 is closed. Then a capacitor 6 is charged by an AC voltage source 8 via a transformer 4 and a rectifier circuit 5. The output 201 is turned off at a previously set time point t1 to open the switch 12. At the same time, the output 202 of the circuit 71 is turned on to close a switch 13. Here the capacitor 6 is charged again by an AC voltage source 9 via the transformer 4 and the circuit 5. Therefore the maximum current level can be reduced at the beginning and at a time point t1 respectively by selecting properly the voltage levels of both sources 8 and 9, the resistance values of resistances 10 and 11 and the time point t1 when the circuit 71 switches both outputs 201 and 202 respectively. |
