| 摘要 |
It is intended to create a drive circuit for GTO thyristors, which supplies the necessary triggering current (turn-on currents) with little losses. In this case, the triggering current is intended to remain largely independent of influences such as manufacturing tolerances, temperature and voltages, and a constant continuous gate current should be available, in an unlimited manner, after an initial triggering current surge. For an arrangement in accordance with the title, which uses triggering pulse transformers with downstream-connected ratification means which (connected in parallel on the secondary side) act on the gate of the GTO thyristor and (on the primary side) are supplied from at least one input voltage and are operated via controllable power switches, this is achieved as follows: the power switches (6, 6') have a current-source function and are designed such that, with the input voltage (Ue1) kept low, they produce the continuous gate current for the GTO thyristor (1) with the triggering pulse transformers (T1, T'1) operating in a push-pull manner on the primary side. A second input voltage (Ue2) at a higher potential is provided for a triggering pulse increase via which a triggering capacitor (11) is charged, controlled via a controllable semiconductor switch (10). Said triggering capacitor (11) is discharged via the controllable power switches (6, 6') at the moment when the GTO thyristor (1) is triggered, with the pulse current sources (6, 6') being overdriven, the primary windings of the triggering pulse transformer (T1, T'1) being in parallel for a triggering current increase, that is to say in common mode ... Original abstract incomplete. <IMAGE>
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