ARC WELDING POWER SUPPLY BUILT AROUND HIGH- FREQUENCY INVERTER Russian patent published in 2000 - IPC

FIELD: welding engineering. SUBSTANCE: power supply has high-frequency semiconductor inverter whose first input is connected to energy source and output, to welding circuit including two welding electrodes connected in parallel with output-voltage sensor and series-connected welding-current sensor; it has control unit incorporating voltage-to-control-pulse-period-length converter, specified voltage supply, multiplier, welding current setting potentiometer, and error amplifier. Mean current measured at power supply output is compared with setting voltage across mentioned potentiometer; used as control signal for setting welding current is result of subtraction of output voltage and specified voltage. Comparison result in the form of definite voltage is converted into length of periods of control pulses used as feedback for controlling the inverter. Optimal relationships between arc voltage, short-circuit current, and welding current at different welding current settings ensure high quality of welds, reduced splashing of metal, and improved transfer of its droplets to bath. EFFECT: improved precision of controlling output parameters of power supply. 3 dwg