Method for producing an arc detection signal and arc detection arrangement

Patent metadata

Field	Value
Publication number	US-10209294-B2
Application number	US-201314097428-A
Country	US
Kind code	B2
Filing date	Dec 5, 2013
Priority date	Jun 7, 2011
Publication date	Feb 19, 2019
Grant date	Feb 19, 2019

Abstract

A method for producing an arc detection signal on the basis of a plurality of observation signals comprises producing an arc detection part-signal for each of at least two observation signals. Producing each of the part-signals includes correlating the respective observation signal with a correlation signal by influencing the correlation signal with the respective observation, thereby producing a correlation result; producing or modifying a coefficient on the basis of the correlation result; and weighting the respective observation signal with the coefficient. The arc detection part-signals are added to form the arc detection signal.

First claim

What is claimed is:

1. A method of producing an arc detection signal for a plasma system on the basis of a plurality of observation signals, the method comprising:
producing, by an arc detection system, an arc detection part-signal for each of at least two observation signals, each observation signal being generated based on a respective measurement signal of the plasma system, at least one of the observation signals being generated by the respective measurement signal being amplified, filtered, differentiated according to time, normalized with noise thereof, or mathematically processed, at least one of the observation signals having a corresponding indication for an arc in the plasma system, the production of each arc detection part-signal comprising:
correlating, by the arc detection system, the respective observation signal or a modified observation signal with a respective correlation signal to produce a correlation result, at least one of the correlation signals being one of a signal related to a previously established arc detection signal, an arc detection signal which establishes an arc detection in an independent manner, and an externally produced signal;
producing, by the arc detection system, or modifying a respective coefficient for the arc detection part-signal on the basis of the correlation result; and
weighting, by the arc detection system, the respective observation signal with the respective coefficient to produce the arc detection part-signal; and

adding, by the arc detection system, the arc detection part-signals to form the arc detection signal for detecting whether an arc is present in the plasma system.

2. The method of claim 1 , wherein the correlation result is multiplied with a factor and is added with a correct preceding sign to the coefficient to form an updated coefficient.

3. The method of claim 1 , wherein the arc detection signal is supplied to a decision member and an output signal of the decision member is used as the correlation signal for at least one of the observation signals.

4. The method of claim 1 , wherein, in a decision member, the arc detection signal is compared with one or more thresholds, provided with an offset and/or a non-linearity that is applied to the arc detection signal.

5. The method of claim 1 , wherein at least one modified observation signal is obtained by the respective observation signal being compared with at least one threshold or applied with a non-linearity.

6. The method of claim 1 , wherein a size of at least one coefficient is limited.

7. The method of claim 1 , wherein the coefficients are normalized.

8. The method of claim 1 , wherein at least one coefficient is corrected for selective overvaluation or undervaluation of the observation signal which is weighted therewith.

9. The method of claim 1 , wherein at least one coefficient is acted on with a shrinkage.

10. The method of claim 1 , wherein at least one observation signal is weighted with a plurality of coefficients.

11. The method of claim 10 , wherein at least one observation signal is weighted with the coefficients after different time delays.

12. An arc detection system for a plasma system, the arc detection system comprising a combiner to which a plurality of observation signals are supplied, the combiner comprising:
at least two arc detection part-signal generators to each of which an observation signal is supplied, each arc detection part-signal generator being configured to generate an arc detection part-signal, each observation signal being generated based on a respective measurement signal of the plasma system, at least one of the observation signals being generated by the respective measurement signal being amplified, filtered, differentiated according to time, normalized with noise thereof, or mathematically processed, at least one of the observation signals having a corresponding indication for an arc in the plasma system, each arc detection part-signal generator comprising:
a multiplier configured to multiply the observation signal with a coefficient to produce the arc detection part-signal;
a correlator configured to correlate the observation signal with a respective correlation signal to produce a correlation result, at least one of the correlation signals being one of a signal related to a previously established arc detection signal, an arc detection signal which establishes an arc detection in an independent manner, and an externally produced signal; and
a coefficient producer which is connected to the correlator and the multiplier and is configured to produce the coefficient based on the correlation result; and

an adder connected to each of the arc detection part-signal generators to receive the arc detection part-signals and generate the arc detection signal for detecting whether an arc is present in the plasma system.

13. The arc detection system of claim 12 , wherein the coefficient producer comprises an integrator.

14. The arc detection system of claim 12 , comprising a normalization member, to which the coefficients are supplied and whose output is connected in each case to a multiplier in the coefficient producers.

15. The arc detection system of claim 12 , comprising a decision member arranged downstream of the combiner, the decision member being configured to supply an output to the correlators.

16. The arc detection system of claim 12 , wherein at least one arc detection part-signal generator comprises a plurality of time-delay members, correlators and coefficient producers.

Assignees

• Trumpf Huettinger Gmbh Co Kg

Inventors

• Bannwarth Markus
• Fritsch Christian
• Heller Ulrich
• Krausse Daniel
• Merte Rolf
• Nitschke Moritz
• Wiedemuth Peter
• Bock Christian
• Glueck Michael
• Kirchmeier Thomas
• Mann Ekkehard
• Nedunuri Krishna Kishore
• Steuber Martin
• Winterhalter Markus

Classifications

• H01J37/32944 Primary

  Arc detection · CPC title

• G01R31/24 Primary

  Testing of discharge tubes (during manufacture H01J9/42) · CPC title