Extinguishing device for main thyristors and DC voltage control unit - has two main and two extinguishing thyristors and two diodes shunted by capacitors

摘要

The voltage control unit generates a variable voltage from a constant voltage, for two-quadrant operation with current reversal. An extinguishing capacitor (k5) one electrode is connected to the junction point between two extinguishing thyristors (n91, n92) between the constant voltage source terminals. Its other electrode is connected to the junction point between two diodes (n93, n94) also connected to the constant voltage terminals. A capacitor (k1, k2) is in parallel with each diode (n93, n94). A transformer winding (t1-t6) is in series with each thyristor (n81-m82; n91, n92) and each diode (n93, n94). Direction of winding of all windings (t1-t6) is the same.