| 摘要 |
The proposed digital device is intended to control a multiphase thyristor-pulse d.c. converter and comprises two decoders, each having as many main outputs as there are phases to that of the connector, and auxiliary outputs which alternate with the main outputs. The device further includes a clock pulse counter whose outputs are connected to inputs of the decoders, and a reversible counter whose add and subtract inputs are connected to outputs of a control unit, outputs of the reversible counter being connected to inputs of the second decoder. The device further includes a NOT gate and an OR gate having all of its inputs connected to an emergency output of a respective phase of the converter an output of said OR gate being connected to an input of the NOT gate. The device further includes two recalculation units, each comprising main AND gates equal in number to the number of phases of the converter, their first inputs being connected to an output of the NOT gate, a second input of each of said AND gates being connected to a respective main output of the respective decoder, and an output of each of said AND gates being connected to a control electrode of a respective thyristor of the respective phase of the converter. Emergency AND gates are divided into groups in a number equal to the number of phases of the converter, the number of said emergency AND gates in each group being equal to the number of auxiliary outputs of the respective decoder. In each group, a first input of each of said emergency AND gates is connected to a respective auxiliary output of the respective decoder. Second inputs of all the emergency AND gates in each group are connected to an emergency output of a respective phase of the converter. A control electrode of a respective thyristor of each of the remaining phases of the converter is connected to an output of a respective emergency AND gate. When operating under emergency conditions, when one of the converter's phases is out of operation, the device provides for equal time intervals between the instants the thyristors of the rest of the converter's phases are driven into conduction.
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