Welding power supply with digital control of duty cycle
AssigneeIllinois Tool Works Inc.
InventorBernard J. Vogel
Life of this patent
Estimating the term…
Abstract
A welding power supply including power conversion circuitry adapted to receive a primary source of power, to utilize one or more power semiconductor switches to chop the primary source of power, and to convert the chopped power to a welding output is provided. The provided welding power supply includes a pulse width modulated (PWM) digital controller including gate drive circuitry that generates a PWM output signal that controls the switching of the one or more power semiconductor switches. The PWM output signal includes a duty cycle term corrected for one or more sources of error in the welding system.
Claims20
A digital pulse width modulated (PWM) controller for a switched mode welding power supply configured to:
- determine an output voltage term of the switched mode welding power supply;
- calculate a variable bus voltage term of the switched mode welding power supply;
- calculate a proportional error term that corrects for a difference between a commanded current level and an actual output current level of the welding power supply;
- and
- compute a duty cycle term by combining the determined output voltage term, the calculated variable bus voltage term, and the proportional error term.
A welding power supply, comprising:
- power conversion circuitry comprising one or more power semiconductor switches, wherein the power conversion circuitry is configured to receive power from a primary source and to switch the one or more power semiconductor switches between an ON configuration and an OFF configuration to convert the received power to a welding output;
- and
- a pulse width modulated (PWM) digital controller coupled to the power conversion circuitry and configured to calculate a duty cycle term for control of switching of the one or more semiconductor switches by computing an integral term configured to correct for steady state error between a commanded current level and an actual output current level.
A welding power supply, comprising:
- power conversion circuitry comprising one or more power semiconductor switches configured to receive power from a primary source and to switch the one or more power semiconductor switches between an ON configuration and an OFF configuration to convert the received power to a welding output;
- and
- a pulse width modulated (PWM) digital controller coupled to the power conversion circuitry and configured to calculate a duty cycle term that is corrected with a droop term that corrects for the non-ideal transfer function of the welding power supply.
Dependencies are inferred from the claim text.