Systems and methods to control pulse welding

Patent metadata

Field	Value
Publication number	US-2020122263-A1
Application number	US-201916653503-A
Country	US
Kind code	A1
Filing date	Oct 15, 2019
Priority date	Oct 19, 2018
Publication date	Apr 23, 2020
Grant date	—

Abstract

Systems and methods to control pulse welding are disclosed. An example welding-type system includes: power conversion circuitry configured to convert input power to welding-type power; and control circuitry configured to control the power conversion circuitry to output the welding-type power in a plurality of pulse cycles, each pulse cycle including background, ramp up, peak, and ramp down phases. Controlling the power conversion circuitry involves: during the background phase, controlling the power conversion circuitry in a voltage-controlled mode using a background voltage as a target voltage; during the ramp up phase, controlling the power conversion circuitry by changing the target voltage to a peak voltage; during the peak phase, controlling the power conversion circuitry using the peak voltage as the target voltage; and during the ramp down phase, controlling the power conversion circuitry by changing the target voltage to the background voltage.

First claim

What is claimed is:

1 . A welding-type system, comprising:
power conversion circuitry configured to convert input power to welding-type power; and control circuitry configured to control the power conversion circuitry to output the welding-type power in a plurality of pulse cycles, each pulse cycle comprising a background phase, a ramp up phase, a peak phase, and a ramp down phase, wherein the controlling the power conversion circuitry comprises:
during the background phase of the pulse cycles, controlling the power conversion circuitry in a voltage-controlled mode using a background voltage as a target voltage;
during the ramp up phase of the pulse cycles, controlling the power conversion circuitry in the voltage-controlled mode by changing the target voltage to a peak voltage;
during the peak phase of the pulse cycles, controlling the power conversion circuitry in the voltage-controlled mode using the peak voltage as the target voltage; and
during the ramp down phase of the pulse cycles, controlling the power conversion circuitry in the voltage-controlled mode by changing the target voltage to the background voltage.

2 . The welding-type system as defined in claim 1 , wherein the control circuitry is configured to change the target voltage from the background voltage to the peak voltage at the start of the ramp up phase.

3 . The welding-type system as defined in claim 1 , wherein the control circuitry is configured to change the target voltage from the peak voltage to the background voltage at the start of the ramp down phase.

4 . The welding-type system as defined in claim 1 , wherein the control circuitry is configured to control the power conversion circuitry in the voltage-controlled mode by controlling the power conversion circuitry based on comparing an output voltage of the power conversion circuitry to the target voltage.

5 . The welding-type system as defined in claim 1 , wherein the control circuitry is configured to:
control the power conversion circuitry using a first output inductance during the peak phase and the background phase; and control the power conversion circuitry using a second output inductance during the ramp up phase and the ramp down phase.

6 . The welding-type system as defined in claim 5 , wherein the second output inductance is higher than the first output inductance.

7 . The welding-type system as defined in claim 5 , wherein the second output inductance is lower than the first output inductance.

8 . The welding-type system as defined in claim 5 , wherein the control circuitry is configured to adjust the second output inductance based on at least one of an output voltage at an end of the peak phase, a time at which the output voltage was within a threshold voltage of the peak voltage during the peak phase, or a voltage overshoot of the peak voltage or the background voltage.

9 . The welding-type system as defined in claim 5 , wherein the control circuitry is configured to:
control the power conversion circuitry using the first output inductance by controlling an output current based on a first relationship between an output voltage of the power conversion circuitry and rate of output current change; and control the power conversion circuitry using the second output inductance by controlling an output current based on a second relationship between the output voltage of the power conversion circuitry and the rate of output current change.

10 . A welding-type system, comprising:
power conversion circuitry configured to convert input power to welding-type power; and control circuitry configured to control the power conversion circuitry to output the welding-type power in a plurality of pulse cycles, each pulse cycle comprising a background phase, a ramp up phase, a peak phase, and a ramp down phase, wherein the controlling the power conversion circuitry comprises controlling the power conversion circuitry in a voltage-controlled mode by changing a target voltage based on which of the background phase, the ramp up phase, the peak phase, or the ramp down phase of the pulse cycle is being controlled.

11 . A method for pulse welding, the method comprising:
controlling, via control circuitry, power conversion circuitry to convert input power to output welding-type power in a plurality of pulse cycles, each pulse cycle comprising a background phase, a ramp up phase, a peak phase, and a ramp down phase, wherein the controlling the power conversion circuitry comprises:
during the background phase of the pulse cycles, controlling the power conversion circuitry in a voltage-controlled mode using a background voltage as a target voltage;
during the ramp up phase of the pulse cycles, controlling the power conversion circuitry in the voltage-controlled mode by changing the target voltage to a peak voltage;
during the peak phase of the pulse cycles, controlling the power conversion circuitry in the voltage-controlled mode using the peak voltage as the target voltage; and
during the ramp down phase of the pulse cycles, controlling the power conversion circuitry in the voltage-controlled mode by changing the target voltage to the background voltage.

12 . The method as defined in claim 11 , wherein changing the target voltage to the peak voltage occurs at the start of the ramp up phase.

13 . The method as defined in claim 11 , wherein changing the target voltage to the background voltage occurs at the start of the ramp down phase.

14 . The method as defined in claim 11 , wherein controlling the power conversion circuitry in the voltage-controlled mode comprises controlling the power conversion circuitry based on comparing an output voltage of the power conversion circuitry to the target voltage.

15 . The method as defined in claim 11 , wherein controlling the power conversion circuitry comprises:
controlling the power conversion circuitry using a first output inductance during the peak phase and the background phase; and controlling the power conversion circuitry using a second output inductance during the ramp up phase and the ramp down phase.

16 . The method as defined in claim 15 , wherein the second output inductance is higher than the first output inductance.

17 . The method as defined in claim 15 , wherein the second output inductance is lower than the first output inductance.

18 . The method as defined in claim 15 , further comprising adjusting the second output inductance based on at least one of an output voltage at an end of the peak phase, a time at which the output voltage was within a threshold voltage of the peak voltage during the peak phase, or a voltage overshoot of the peak voltage or the background voltage.

19 . The method as defined in claim 15 , wherein controlling the power conversion circuitry using the first output inductance comprises controlling an output current based on a first relationship between an output voltage of the power conversion circuitry and rate of output current change, and controlling the power conversion circuitry using the second output inductance comprises controlling an output current based on a second relationship between the output voltage of the power conversion circuitry and the rate of output current change.

Assignees

• Illinois Tool Works

Inventors

• Knoener Craig Steven
• Johnson Lucas Charles
• Macmullen Zach W
• Tyler Charles Ace
• Dong Christine

Classifications

• B23K9/095 Primary

  Monitoring or automatic control of welding parameters · CPC title

• B23K9/1043

  characterised by the electric circuit (B23K9/1012 takes precedence) · CPC title

• B23K9/091

  characterised by the circuits · CPC title

• B23K9/092

  characterised by the shape of the pulses produced · CPC title

• B23K9/0732

  Stabilising of the arc current · CPC title