| 摘要 |
A method of starting a current-fed inverter used as a high-frequency induction heating power supply and having a DC cut-off capacitor in the load circuit first supplies successive gate pulses which are spaced apart by small periods of time to a pair of thyristors of a power inverter unit until a turn-on current for the thyristors exceeds a latching current. When a voltage between output terminals of the power inverter unit reaches a predetermined thyristor reverse-biasing voltage, the successive gate pulses are no longer supplied to the thyristor pair. Then, successive gate pulses are supplied to a another pair of thyristors of the power inverter unit. The foregoing operation is repeated for successive thyristor pairs in a predetermined order until the period of oscillation of successive gate pulses supplied to the thyristor pairs is progressively shortened into conformity with a prescribed inverter oscillation period. With this method, no starter (with separate power supply) is required, and the prescribed inverter oscillation period can be quickly and reliably reached.
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