[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Streamer length vs. power delivery time...



Original poster: Terry Fritz <teslalist@xxxxxxxxxxxxxxxxxxxxxxx>

Hi Steve,


At 09:35 PM 6/18/2005, you wrote:
Hi Terry,

............

Also, there is NO energy left in the primary 1 cycle after the driver
is shut off (the current hits zero fast).  Pspice did NOT match this
with the 6p+220k streamer, in fact it took maybe another 6-7 cycles
before the current hit zero.  Something isnt right with the model
yet...
.........

How does this look:

http://hot-streamer.com/temp/SteveCurrentShutdown.gif

I simply made Vin = -Vin after the well time shut down.... I always thought it should have been like that,... but I didn't bother since it did not change the top voltage hardly at all. However, it does have a drastic (and apparently very realistic) effect on primary current!!!

Sort of a boo boo on my part, but a trivial fix....

The latest (Like 5 minutes old) version with this fix is at:

http://drsstc.com/~terrell/modeling/scantesla623.ZIP

Let me know if this looks more like your real primary current readings. I may not have the same coil setup as you programmed into the model since I was playing with things (listed below) but it should be close. I am not sure how to fix MicroSim for this case... Not sure I care much about MicroSim anymore ;-))) But if the drive goes open, the antiparallel diodes should do the same thing.

I guess the model should zero out X0[4] (primary current sending energy back to coil) when the current is going in the wrong direction (sending energy to coil at less than Vrail volts) after the shutdown to act like a true diode... That has a low effect, but it would be more correct...

===========================
* ScanTesla Parameter Input File
*
* This file should be in the same directory as the program.
*
* Lines starting with "*" are ignored.
*
* The program expects the parameters in order and as shown.
*
* Cprimary (farads) - start, stop, Inc
450.0e-9
450.0e-9
1.0e-9
* Rprimary (ohms) - Start, Stop, Inc
0.5
0.5
0.1
* Lprimary (heneries) - Start, Stop, Inc
12.45e-6
12.45e-6
0.01e-6
* Lsecondary (heneries) - Start, Stop, Inc
130.0e-3
130.0e-3
1.0e-3
* Coupling - Start, Stop, Inc
0.18
0.18
0.001
* Rsecondary (ohms) - Start, Stop, Inc
500.0
500.0
1.0
* Csecondary (farads) - Start, Stop, Inc
38.0e-12
38.0e-12
1.0e-13
* Cload (farads) - Start, Stop, Inc
6.0e-12
6.0e-12
1.0e-12
* Rload (ohms) - Start, Stop, Inc
220.0e3
220.0e3
1.0e3
* Time (sec) - Start, Stop, Inc - If Inc < 0 then automatic timing is used
0.0
500e-6
-100.0e-9
* Vrail - DRSSTC Buss Rail Voltage (volts) - 0.0 for a conventional coil.
400.0
* VCprimary Initial Value (volts) - Primary capacitor voltage for a conventional coil. 0.0 for a DRSSTC.
0.0
*Dwell Time (sec) - DRSSTC T1 time. Ignored for conventional coil.
175.0e-6
* DRSSTC Current Limit (amps) - Set very high for conventional coil.
1000.0e0
* Bang Energy Limit (joules)
100.0
* Goal Type - 0=find maximum VCsecondary 1=find maximum streamer energy
0
*
==================================


Cheers,

        Terry