Waveform compensation systems and methods for secondary weld component response

Patent metadata

Field	Value
Publication number	US-10464155-B2
Application number	US-201615341741-A
Country	US
Kind code	B2
Filing date	Nov 2, 2016
Priority date	Jan 31, 2013
Publication date	Nov 5, 2019
Grant date	Nov 5, 2019

Abstract

A method includes receiving data corresponding to a voltage level over time and a current level over time. The method also includes determining a first ratio corresponding to a voltage ramp percent or a voltage falling edge percent with respect to a peak in the voltage level and determining a second ratio corresponding to a current ramp ratio or a current falling edge ratio with respect to a peak in the current level. The method further includes determining, based on a comparison between the first ratio and the second ratio, whether to increment, decrement, or maintain an inductance compensation estimation value corresponding to an estimated inductance present in one or more secondary components associated with the welding operation.

First claim

The invention claimed is:

1. A method, comprising:
receiving first data corresponding to a first weld waveform generated during a welding operation, wherein the first weld waveform corresponds to a voltage level over time;
receiving second data corresponding to a second weld waveform generated during the welding operation, wherein the second weld waveform corresponds to a current level over time;
determining, based on the first data, a first ratio corresponding to a voltage ramp ratio or a voltage falling edge ratio with respect to a peak in the first weld waveform;
determining, based on the second data, a second ratio corresponding to a current ramp ratio or a current falling edge ratio with respect to a peak in the second weld waveform;
determining, based on a comparison between the first ratio and the second ratio, a voltage for the welding operation that compensates for an inductance level present in one or more secondary components associated with the welding operation; and
controlling the welding operation in accordance with the determined voltage.

2. The method of claim 1 , wherein the first ratio corresponds to the voltage ramp ratio and determining the voltage ramp ratio comprises dividing a normalized ramp voltage by a normalized peak voltage.

3. The method of claim 1 , wherein the second ratio corresponds to the current ramp ratio and determining the current ramp ratio comprises dividing a normalized ramp current by a normalized peak current.

4. The method of claim 1 , wherein determining the voltage for the welding operation comprises calculating a voltage error and subtracting the voltage error from a measured voltage.

5. The method of claim 4 , wherein calculating the voltage error comprises multiplying an incremented inductance value by the derivative of current with respect to time.

6. The method of claim 1 , wherein the first ratio corresponds to the voltage falling edge ratio and determining the voltage falling edge ratio comprises dividing a normalized falling edge voltage by a normalized peak voltage.

7. The method of claim 1 , wherein the second ratio corresponds to the current falling edge ratio and determining the current falling edge ratio comprises dividing a normalized falling edge current by a normalized peak current.

8. A method, comprising:
receiving first data corresponding to a first weld waveform generated during a welding operation, wherein the first weld waveform corresponds to a voltage level over time;
receiving second data corresponding to a second weld waveform generated during the welding operation, wherein the second weld waveform corresponds to a current level over time;
determining, based on the first data, a first ratio corresponding to a voltage ramp ratio or a voltage falling edge ratio with respect to a peak in the first weld waveform;
determining, based on the second data, a second ratio corresponding to a current ramp ratio or a current falling edge ratio with respect to a peak in the second weld waveform;
determining, based on a comparison between the first ratio and the second ratio, whether to increment, decrement, or maintain an inductance compensation estimation value corresponding to an estimated inductance present in one or more secondary components associated with the welding operation; and
controlling the welding operation based at least in part on the induction compensation estimation value.

9. The method of claim 8 , comprising calculating a voltage for the welding operation by subtracting a voltage error term from a measured voltage, wherein the voltage error term accounts for an estimated voltage rise corresponding to the estimated inductance.

10. The method of claim 9 , wherein the voltage error term comprises the inductance compensation estimation value multiplied by the derivative of the current level over time.

11. The method of claim 8 , wherein determining the voltage ramp ratio or the voltage falling edge ratio comprises dividing a normalized ramp or falling edge voltage by a normalized peak voltage.

12. The method of claim 8 , wherein determining the current ramp ratio or the current falling edge ratio comprises dividing a normalized ramp or falling edge current by a normalized peak current.

13. A welding system, comprising:
power conversion circuitry configured to convert primary power to welding power for a welding operation; and
a weld controller configured to:
receive first data corresponding to a first weld waveform generated during a welding operation, wherein the first weld waveform corresponds to a voltage level over time;
receive second data corresponding to a second weld waveform generated during the welding operation, wherein the second weld waveform corresponds to a current level over time;
determine, based on the first data, a first ratio corresponding to a voltage ramp ratio or a voltage falling edge ratio with respect to a peak in the first weld waveform;
determine, based on the second data, a second ratio corresponding to a current ramp ratio or a current falling edge ratio with respect to a peak in the second weld waveform;
determine, based on a comparison between the first ratio and the second ratio, a voltage for the welding operation that compensates for an inductance level present in one or more secondary components associated with the welding operation; and
control the power conversion circuitry to perform the welding operation in accordance with the determined voltage.

14. The welding system as defined in claim 13 , wherein the first ratio corresponds to the voltage ramp ratio and determining the voltage ramp ratio comprises dividing a normalized ramp voltage by a normalized peak voltage.

15. The welding system as defined in claim 13 , wherein the second ratio corresponds to the current ramp ratio and determining the current ramp ratio comprises dividing a normalized ramp current by a normalized peak current.

16. The welding system as defined in claim 13 , determining the voltage for the welding operation comprises calculating a voltage error and subtracting the voltage error from a measured voltage.

17. The welding system as defined in claim 16 , wherein calculating the voltage error comprises multiplying an incremented inductance value by the derivative of current with respect to time.

18. The welding system as defined in claim 13 , wherein the first ratio corresponds to the voltage falling edge ratio and determining the voltage falling edge ratio comprises dividing a normalized falling edge voltage by a normalized peak voltage.

19. The welding system as defined in claim 13 , wherein the second ratio corresponds to the current falling edge ratio and determining the current falling edge ratio comprises dividing a normalized falling edge current by a normalized peak current.

Assignees

• Illinois Tool Works

Inventors

• Davidson Robert R
• Bunker Thomas A
• Schuh Richard

Classifications

• B23K9/095

  Monitoring or automatic control of welding parameters · CPC title

• G01R19/2506

  Arrangements for conditioning or analysing measured signals, e.g. for indicating peak values (G01R19/003 takes precedence); Details concerning sampling, digitizing or waveform capturing (displaying waveforms G01R13/00; analog sampling G01R19/0053) · CPC title

• B23K9/0953

  using computing means · CPC title

• B23K9/09 Primary

  Arrangements or circuits for arc welding with pulsed current or voltage · CPC title

• B23K9/1006 Primary

  Power supply · CPC title