Abstract: In some aspects, power supplies for liquid cooled plasma cutting systems configured to support plasma arc generation by a torch head connected to the power supply can include: a set of electrical components for plasma arc generation; and a power supply housing containing the set of electrical components, the power supply housing having a front panel and at least two side panels and defining: a set of inlets for allowing a cooling gas to enter the power supply housing to thermally regulate the set of electrical components, at least one inlet of the set of inlets being positioned at a corner of the housing and oriented at a non-zero angle relative to the front panel and to at least one of the two side panels; and a set of vents for allowing at least a portion of the cooling gas to exit the power supply housing.

Abstract: A plasma cutting system includes a plasma torch having a head, and a housing. A power supply is disposed within the housing and is in communication with the plasma torch. The power supply is configured to provide an output current for generating and maintaining a plasma cutting arc by the plasma torch, and includes a control processor in communication with a plurality of autonomous switching circuits via a multi-node communications bus. Each of the autonomous switching circuits includes a microcontroller configured to control the generation of a portion of the output current based on messages received from the control processor, monitor operating parameters of the autonomous switching circuit, and modify a control parameter of the autonomous switching circuit independent of and asynchronous to the other autonomous switching circuits of the plurality of autonomous switching circuits when one or more of the operating parameters exceeds a predetermined threshold.

Abstract: A plasma arc cutting system includes a power supply comprising a multi-pulse transformer and a plurality of semiconductor switches directly connected to a bank of capacitors, and a thermal regulation system connected to the power supply and configured to cool the multi-pulse transformer. The thermal regulation system includes a cold plate in direct contact with the semiconductor switches; a fluid conduit disposed within the cold plate; and a pump connected to the conduit and configured to direct a coolant fluid through the conduit. The power supply has at least one of the following operating requirements: (i) a weight to power ratio of approximately 22.4 pounds per kilowatt; (ii) a volume to power ratio of approximately 1366 cubic inches per kilowatt; (iii) an average semiconductor device case temperature of approximately 100 degrees Centigrade during a cutting operation; (iv) a maximum transformer temperature of about 133 degrees Centigrade during a cutting operation.

Abstract: In some aspects, power supplies for liquid cooled plasma cutting systems configured to support plasma arc generation by a torch head connected to the power supply can include: a set of electrical components for plasma arc generation; and a power supply housing containing the set of electrical components, the power supply housing having a front panel and at least two side panels and defining: a set of inlets for allowing a cooling gas to enter the power supply housing to thermally regulate the set of electrical components, at least one inlet of the set of inlets being positioned at a corner of the housing and oriented at a non-zero angle relative to the front panel and to at least one of the two side panels; and a set of vents for allowing at least a portion of the cooling gas to exit the power supply housing.

Abstract: A plasma cutting system includes a plasma torch having a head, and a housing. A power supply is disposed within the housing and is in communication with the plasma torch. The power supply is configured to provide an output current for generating and maintaining a plasma cutting arc by the plasma torch, and includes a control processor in communication with a plurality of autonomous switching circuits via a multi-node communications bus. Each of the autonomous switching circuits includes a microcontroller configured to control the generation of a portion of the output current based on messages received from the control processor, monitor operating parameters of the autonomous switching circuit, and modify a control parameter of the autonomous switching circuit independent of and asynchronous to the other autonomous switching circuits of the plurality of autonomous switching circuits when one or more of the operating parameters exceeds a predetermined threshold.

Abstract: In some aspects, plasma torch cutting systems can include a housing and a plasma torch power supply within the housing and configured to generate a signal that initiates generation of a plasma arc in a torch head, the power supply including an integrated circuit comprising a plurality of electronic components used to generate the signal that initiates generation of the plasma arc, at least one of the electronic components being at least partially formed of a wide bandgap semiconductor material.

Abstract: In some aspects, plasma torch cutting systems can include a housing and a plasma torch power supply within the housing and configured to generate a signal that initiates generation of a plasma arc in a torch head, the power supply including an integrated circuit comprising a plurality of electronic components used to generate the signal that initiates generation of the plasma arc, at least one of the electronic components being at least partially formed of a wide bandgap semiconductor material.

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 method and apparatus for controlling a gas supply to a plasma arc torch uses a proportional control solenoid valve positioned adjacent the torch to manipulate the gas flow to the torch, thereby extending electrode life during arc transfer and shutdown. Swirl ring design can be simplified and gas supply and distribution systems become less complicated. The invention also allows manipulation of shield gas flow to reduce divot formation when making interior cuts. The system can be controlled with a digital signal processor utilizing a feedback loop from a sensor.

Abstract: A plasma arc cutting system includes a power supply comprising a multi-pulse transformer and a plurality of semiconductor switches directly connected to a bank of capacitors, and a thermal regulation system connected to the power supply and configured to cool the multi-pulse transformer. The thermal regulation system includes a cold plate in direct contact with the semiconductor switches; a fluid conduit disposed within the cold plate; and a pump connected to the conduit and configured to direct a coolant fluid through the conduit. The power supply has at least one of the following operating requirements: (i) a weight to power ratio of approximately 22.4 pounds per kilowatt; (ii) a volume to power ratio of approximately 1366 cubic inches per kilowatt; (iii) an average semiconductor device case temperature of approximately 100 degrees Centigrade during a cutting operation; (iv) a maximum transformer temperature of about 133 degrees Centigrade during a cutting operation.

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 method and apparatus for controlling a gas supply to a plasma arc torch uses a proportional control solenoid valve positioned adjacent the torch to manipulate the gas flow to the torch, thereby extending electrode life during arc transfer and shutdown. Swirl ring design can be simplified and gas supply and distribution systems become less complicated. The invention also allows manipulation of shield gas flow to reduce divot formation when making interior cuts. The system can be controlled with a digital signal processor utilizing a feedback loop from a sensor.

Abstract: Described are methods and systems for using a planar inductor that includes a magnetically conductive core, a first planar coil and a second planar coil. The first and second planar coils are attached to a first bridge, located about the core, and are composed of a conductive material. The first and second planar coils have at least one thermally conductive surface exposed to cooling fluid. The first planar coil, the first bridge and the second planar coil are formed from a first unitary section of conductive material. The second planar coil is positioned relative to the first planar coil in a spaced relationship, which is defined by a thickness of the first bridge. An upper surface of the first planar coil is oriented toward a lower surface of the second planar coil to define a first cooling channel between the first planar coil and the second planar coil.

Abstract: A method and apparatus for controlling a gas supply to a plasma arc torch uses a proportional control solenoid valve positioned adjacent the torch to manipulate the gas flow to the torch, thereby extending electrode life during arc transfer and shutdown. Swirl ring design can be simplified and gas supply and distribution systems become less complicated. The invention also allows manipulation of shield gas flow to reduce divot formation when making interior cuts. The system can be controlled with a digital signal processor utilizing a feedback loop from a sensor.

Abstract: A method and apparatus for controlling a gas supply to a plasma arc torch uses a proportional control solenoid valve positioned adjacent the torch to manipulate the gas flow to the torch, thereby extending electrode life during arc transfer and shutdown. Swirl ring design can be simplified and gas supply and distribution systems become less complicated. The invention also allows manipulation of shield gas flow to reduce divot formation when making interior cuts. The system can be controlled with a digital signal processor utilizing a feedback loop from a sensor.

Abstract: A system and method is featured for controlling a process parameter of a thermal processing system by estimating an arc voltage between a plasma arc torch tip and a metallic workpiece and controlling the process parameter based on the estimated arc voltage. Particular embodiments include adjusting the height of a plasma torch based on the estimated arc voltage. A system and method is also featured for estimating an arc voltage in a thermal processing system in which a switch mode power supply provides an arc current to generate a plasma arc between a plasma arc torch tip and a metallic workpiece.

Abstract: A method and apparatus is featured for providing linear control of a regulated electrical property (e.g., current or voltage) in a switch mode power supply of a thermal processing system that includes an inductive element and at least one switching element. The method and apparatus feature structure, or steps, for generating a nonlinear model that predict values for a regulated electrical property of the inductive element based on a given duty cycle of the at least one switching element and structure, or steps, for generating a nonlinear model that determines a duty cycle for the at least one switching element based on the nonlinear predictive model for the regulated electrical property, the nonlinear model determining the duty cycle such that a linear relationship results between the regulated electrical property and a selected value.

Abstract: A method and apparatus for operation of an electrical power conversion system having first and second partial systems connected in parallel. Each partial system includes an inductor and an electronic switch for controlling electrical power transferred through the partial systems. A control circuit controls operation of the electronic switches. The control circuit includes devices for generating a first control signal error and a second control signal error as a function of a reference and current flowing in the inductors. Hysteresis devices receive the first and second control signal errors and provide first and second outputs, respectively, upon intersection of the first and second control signal errors with selected threshold values. Delay devices coupled to the electronic switches receive and delay transmission of the first and second outputs to the electronic switches.