| 摘要 |
In a circuit for hard driving a GTO, the conductor inductance (L1) and the internal inductance of the GTO (L2) form, together with a first capacitor (C1) situated in parallel via a switch (S), a series oscillatory circuit inside the gate circuit. In this connection, the chosen sizes of the first capacitor (C1) and of the first inductance (L1) are such that, if the first capacitor (C1) discharges via the two inductances (L1, L2), the gate current originating from the first capacitor (C1) exceeds half the value of a GTO anode current to be turned off within less than 5 .mu.s in the first quarter oscillation of the series oscillatory circuit. Moreover, first means are provided which uncouple the first capacitor (C1) from the generation of the gate current after the first quarter oscillation of the oscillatory circuit and allow the gate current to decay slowly in such a way that, at any time, it is greater than the tail current of the GTO. Finally, second means are provided in the form of a recharging circuit, which means are activated during the decay of the gate current and apply a holding current (VH) which is sufficient for blocking to the gate (G) of the GTO after the decay of the gate current. (Figure 5)
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