| 摘要 |
PROBLEM TO BE SOLVED: To provide an inverter which can initially start operation with a current smaller than a starting current by building up its output voltage to a predetermined value after declining the output voltage before an overcurrent protective circuit operates when a current is supplied to a load which requires a large driving current in starting. SOLUTION: Pulse signals having different polarities are generated by a two phase waveform generating circuit 2 in accordance with a pulse signal from an oscillation circuit 1 and FET's 3-6 are turned on/off to generate an AC voltage and a voltage corresponding to a rush current at the point is produced by a resistor 9. If the rush current is larger than a set current, the width of the pulse signal outputted by the oscillation circuit 1 is narrowed by a buffer circuit 10 to decline the AC voltage generated by the switching of the FET's 3-6. After a certain lapse of time, the pulse width is widened to generate an AC voltage of 100V and, if a rush current at the point exceeds the set current, the pulse generating of the oscillation circuit 1 is stopped by an overcurrent protective 11 and the generation of the AC 100V by the switching of the FET's is stopped. |
