TRANSPORT VOLTAGE CONVERTER OF DC CONTACT SYSTEM Russian patent published in 1997 - IPC

FIELD: railway transport; rolling stock supplied from DC contact system with pulsed voltage control on traction motors. SUBSTANCE: converter with filter has filter capacitors, first group of isolating diodes and two pulse choppers built around 4-arm thyristor bridges with switching capacitors in output diagonally opposite pairs of junctions. Second group of isolating diodes is introduced additionally. Chopper thyristors are turned ON/OFF by signals from control unit. Voltage across load can be regulated by changing width of pulse at output of each chopper. Maximum width of pulse can be equal to half of cycle. EFFECT: provision of uniform current load on semiconductor devices, reduced change-over switching frequency, reduced power losses. 3 dwg