摘要 |
A high voltage converter apparatus having overvoltage protection circuits for thyristors is disclosed in which, in order to protect series-connected thyristors in the converter against overvoltage, the converter is stopped when the overvoltage is generated by a trouble in the primary circuit of a pulse transformer, which is included in a gate circuit for the thyristors, and one of the overvoltage protection circuits, each of which is connected between an anode and a gate of a corresponding thyristor, is prevented from being operated when the overvoltage is generated by a trouble in the secondary circuit of the pulse transformer. |