Systems and methods providing arc re-ignition for AC arc welding processes

摘要

Systems and methods providing an energy limited arc re-ignition voltage for AC arc welding processes to re-ignite an arc during polarity transitions. In arc welding power source embodiments, configurations of bridge and superposition circuits allow for the directional switching of the welding output current through the welding output circuit path and provide a voltage between the electrode and the workpiece of the welding output circuit path that is sufficient to re-ignite the arc during polarity transition of the output current. The superposition circuit provides a capacitor for storing energy from a dedicated charging source which produces the voltage level for re-igniting the arc during the zero crossing of the output current in both polarities.

主权项

1. A welding power source comprising:
a power conversion circuit configured to convert an input current to an output current; a controller; a bridge circuit operatively connected to the power conversion circuit and configured to switch a direction of the output current through a welding output circuit path operatively connected to a welding output of the welding power source at the command of the controller; and a superposition circuit, including at least one capacitor and at least one dedicated charging source configured to directly or indirectly charge the at least one capacitor, operatively connected to the bridge circuit and configured to provide a voltage between an electrode and a workpiece of the welding output circuit path sufficient for arc re-ignition during polarity transition of the output current.