Digitally controlling thyristor DC converters - by controlling thyristors conductive duration using time shifted and constant pulse trains provided by decoder networks

摘要

The method is for digitally controlling the thyristors of an m-phase thyristor-pulse D;C; converter. The duration of the conductive state of the thyristor for each phase is changed by sending time-shifted and time-constant pulse trains from each of m-control channels to the thyristor. The onset of operations of the thyristor of each phase is shifted 1/m of a thyristor switching period at the same time. In the process of changing the durations of the thyristor's conductive states within the entire control range, each control channel is connected in succession to the thyristor's of the respective pulses on reaching the max. value of the control zone for each channel. A counter driven by a master oscillator supplies pulses to decoder networks which each receive another input from counter. The networks feed a logic network of AND gates to selectively cylically permute the connections from the networks, thus carrying the time shifted pulse train to turn off the thyristors. A decoder network response to counter gives the time constant pulse train.