AUTONOMOUS INVERTER Russian patent published in 1997 - IPC

FIELD: power converters, in particular, thyristor secondary power supplies of middle and large power for arc electric welding. SUBSTANCE: device has two filtering isolating capacitors 3 and 4 with middle point, two inverter cells 5 and 6 which have switching capacitors 7, 8 and chokes 9, 10, thyristors 11, 12 and reverse diodes 13 and 14. In addition device has two output transformers 15 and 16 which have primary windings 17, 18 and secondary windings 19, 20, autonomous load 21 and two dampening diodes 22 and 23. EFFECT: possibility to control output voltage by means of phase regulation ( voltage shape is same as using pulse-width modulation, switching capacity of inverter does not depend on load); this results in possibility for inverter to operate at load jumps; this also results in possibility to generate arbitrary external characteristic of inverter. 2 dwg