CIRCUIT ARRANGEMENT FOR PROTECTING THYRISTORS

摘要

The invention relates to a circuit for protecting a plurality of series-connected thyristors against spontaneous ignition resulting from inadequate release time. For the purpose of individual protection, a device producing a switching signal when the voltage becomes negative is associated with each thyristor. This switching signal is transferred to an evaluating device. This produces a time signal for a monitoring period corresponding to the period of protection of the thyristor. A second switching signal is produced when the voltage becomes positive. When this second stitching signal occurs during the said monitoring period, the ignition circuit is triggered.