Method and circuit arrangement for generating a firing pulse for a converter valve

摘要

Method for generating a firing pulse for a converter valve and a circuit arrangement for carrying out the method. In order to be fired reliably, converter valves have to be driven by a control current having a characteristic which is prescribed in narrow limits. This control current characteristic has a pulse which is as rectangular as possible and a chronologically directly following holding current having a small amplitude. The method according to the invention and the circuit arrangement specified to carry it out are intended to generate the necessary rectangular pulse with as few losses as possible. The novel method for generating a firing pulse for a converter valve has two method steps running synchronously in time, a rising current edge of a sufficient gradient being produced in one method step, while a current amplitude of sufficient magnitude is produced in the other method step. The method is suitable for use in drive circuits which are usually referred to as gate units. <IMAGE>