摘要 |
A static frequency converter comprising an intermediate DC voltage link, a rectifier, and an inverter having main thyristors in a bridge circuit, across which bypass diodes in a bridge circuit are shunted antiparallel, has a quenching circuit shunted across each bridge arm which includes a quenching thyristor, a commutating capacitor, and a commutating choke. There is a common commutating capacitor for each two bridge arms having a common main terminal and an energy-removing device, assigned to each commutating choke, is connected after the potential change has occurred at the corresponding output terminal of the inverter, at the end of each commutation. Energy stored in the commutating choke is taken out by the energy-removing device and over-voltage of the commutating capacitors is prevented. |