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Y. Shi et al.
Fig. 10.13 Root-mean-square of the electrical signal
Fig. 10.14 Kurtosis of the electrical signal. a Kurtosis of arc current. b Kurtosis of arc voltage
2–4, 6–7.5, 15.5–16.5 and 19–20 kHz, among which the first frequency band at
2–4 kHz has the most power.
As Fig. 10.15 shows the largest power, among the four frequency bands is concentrated within the 2–4 kHz band. Figure 10.16 shows the power spectrum in the range
of 2–4 kHz of current signals in the tests by Ti. According to Fig. 10.16, not only
similar are the power spectra in Band 1 under different weld states, but a frequency
delay exists. By changing the welding current from 500 to 560 A, different states of
Y. Shi et al.
Fig. 10.13 Root-mean-square of the electrical signal
Fig. 10.14 Kurtosis of the electrical signal. a Kurtosis of arc current. b Kurtosis of arc voltage
2–4, 6–7.5, 15.5–16.5 and 19–20 kHz, among which the first frequency band at
2–4 kHz has the most power.
As Fig. 10.15 shows the largest power, among the four frequency bands is concentrated within the 2–4 kHz band. Figure 10.16 shows the power spectrum in the range
of 2–4 kHz of current signals in the tests by Ti. According to Fig. 10.16, not only
similar are the power spectra in Band 1 under different weld states, but a frequency
delay exists. By changing the welding current from 500 to 560 A, different states of