Abstract: Transformer flux is monitored to determine if an onset of flux saturation is detected. If flux saturation is not detected, the transformer drive signal is received to a switch that maintains the polarity of the transformer flux. If flux saturation is detected, the transformer drive signal is received by a switch that reverses the polarity of the transformer signal and the transformer flux. This reversal of flux polarity can occur multiple times, during the carrier cycle of the drive signal, without compromising the dynamics of the transformer main control loop or requiring the drive signal to be regenerated.

Abstract: Transformer flux is monitored to determine if an onset of flux saturation is detected. If flux saturation is not detected, the transformer drive signal is received to a switch that maintains the polarity of the transformer flux. If flux saturation is detected, the transformer drive signal is received by a switch that reverses the polarity of the transformer signal and the transformer flux. This reversal of flux polarity can occur multiple times, during the carrier cycle of the drive signal, without compromising the dynamics of the transformer main control loop or requiring the drive signal to be regenerated.

Abstract: A plasma arc torch system includes a plasma arc torch and a positioning apparatus for automated processing of workpieces. In order to maintain consistent cut quality, a controller maintains arc voltage at a predetermined reference value by controlling a standoff between the torch and the workpiece. To prevent contact between the torch and workpiece during kerf crossings and to maintain an optimum standoff during acceleration and deceleration, standoff control override algorithms are implemented in the controller. Additionally, a contact sensing apparatus is provided to automatically retract the torch in the event of contact with the workpiece during processing.