Hi Jan,Your theory and speculations are by no means wild. In fact, I suspect they're spot on.
Oscilloscope measurements of the E-field around a TC show that ground strikes almost instantly remove virtually all of the energy that was previously stored in the ringing secondary:toroid system, while the lighter load of open air streamers allows the secondary to continue ringing for quite some time. The brighter appearance and snappier sound of ground sparks also suggests significantly higher peak current and higher energy density. These provide supporting evidence that ground strikes may be high-current capacitor-like discharges. It's also likely that any high di/dt discharges would shock excite the resulting toroid and ground path LC system. This is known to occur with Marx generators, and VDG discharges (per the paper you referenced), so its likely that it occurs within TC ground discharges.
Jim's suggestion of attempting to estimate the discharge path inductance or measuring the low-voltage ringing frequencies are excellent ones. You may also want to try measuring ground discharge current using a wideband current transformer (CT). The isolation provided by the CT will help to avoid ground bounce artifacts that can be hard to eliminate during high-voltage impulse measurements. Also, you may want to try connecting the grounded side of the measurement gap and measurement resistor to a grounded metal screen counterpoise beneath the TC. This would help others to replicate similar measurements in different environments since the ground path(s) for TC's are often not well-defined or consistent.
Thank you for performing the experiments and sharing them with us! Bert jan@xxxxxxxx wrote:
Hi, I have published another measurement, this time of streamer current impulses of very high amplitude:http://sthlmteslacoil.se/measurements.htmlI have also added some wild speculations, please feel free to comment.Jan Stockholm, Sweden _______________________________________________ Tesla mailing list Tesla@xxxxxxxxxxxxxxxxxx https://www.pupman.com/mailman/listinfo/tesla
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