Development of single-phase high-power factor inverter welding sources

New topologies of single-phase inverter welding supplies with increased power factor are proposed. The need to increase the power factor of welding equipment is dictated by the introduction of modern standards of electromagnetic compatibility of technical equipment. One of the proposed power supplies is built on the basis of a modified forward-current converter, the other is based on a bridge converter. A distinctive feature of the presented power supplies with an increased power factor is the absence of additional inductive power components, a smaller capacity of the smoothing capacitor and a simplified scheme of limiting its charging current. The developed welding power supplies have an increased no-load voltage, which makes it possible to lightly ignite the arc during manual arc welding. Due to the increased power factor, the current consumed from the mains is 30 to 45 % lower than for widely used welding inverters without power factor correction. The presented circuit solutions of the converters allow creating welding inverter power supplies with a high-power factor, having a lower cost and better weight and size characteristics in comparison with professional welding inverters equipped with power factor correctors.