Kapanadze Cousin - DALLY FREE ENERGY

[Hoppy]

Do you have your CSR positioned like shown here or here?
The trace seems to indicate the first option.

The collector current seems to rise at the rate of 7A/μs and the collector supply voltage seems to be 65V  which calculates to 9μH of primary (W1) inductance, if the secondary (W2) is not loaded (or is it 70A/μs and 650V because of the "probe x10" ?)
The horizontal time scale is too dense to see any meaningful change in the slope of this curve, thus the 9μH is probably a mix of the saturated and unsaturated inductances.
Pretty messy but that trace nicely shows the long decay current in the primary winding. This long decay should be caused be the Flyback Diode (D1) working quite well.
I don't like the polarity of that short spike in the beginning, because it indicates that the current is reversing in the CSR.  That should not be possible if the secondary (W2) is disconnected.

Verpies,

CSR was connected as in the first option. W2 was loaded with 50R.

Probe switched to x10 and set x10 on channel menu, so voltage levels as indicated on screen shot - 65V rail.

I'm not convinced that in my case, the toroid is saturating early on in the waveforms curving leading edge. If this were the case why is a heat sink called for both toroid and power transistor? Both me and Itsu can see this curve at low power levels with minimal heating of the transistor. I cannot see how the toroid could even get warm unless the flyback diode went OC. Can you see how the toroid might get very hot in this circuit configuration to warrant the use of high temperature Teflon covered wire and heat sink mounting?

Regards
Hoppy

[d3x0r]

How is C1 supplying the transistor?  e.g.: in common emitter or common collector mode?  Is C1 in the emitter path or in the base path?
Please don't call a transistor U1 (that's reserved for integrated circuits). Let's call your transistors Q1 and Q2, from now on.

ok I'll try and remember.  C1 would be on the collector, and the emitter to the base of the 13009BJT.
Q1 is a bdx53b darlington
Q2 is the E13009

Is that a BJT transistor?  If "yes" then it does not have a "gate". Only FETs have "gates".  BJTs have bases. It's not only  a difference in the name, they also act differently. The base of a BJT acts like a diode (or a resistor) while the gate of a MOSFET acts like a small capacitor.

Also BJTs are not voltage driven - they are current driven. Thus 5V of forward voltage applied into the base will damage Q1 immediately if the current is not limited by a resistor.  BTW: The 5V is most likely the maximum reverse voltage that will not break down your transistor's base-emitter junction in reverse.
Also transistor's max ratings are not indicative of the transistor's transconductance.  To figure out how much collector current (I_C) you will get for a given base current (I_B), use the equation: I_C=I_B*h_FE.
The h_FE parameter is also known as beta (β).  See this article.

The resistor in series with the base works like a voltage to current converter.
For example if you apply 5V to a base through a 2Ω resistor (R_B) then I_B=(V-0.7V)/R_B of current will flow. The 0.7V is the constant voltage drop across the the base-emitter junction.  This calculates to I_B=4.3V/2Ω = 2.2 Amps.
If a transistor, that has a β or h_FE equal to 100, is fed with this 2.15A of current into the base then 215 Amps will flow in its collector (in common emitter configuration).

Does that answer your questions?

maybe... so it's more likely to reduce the current than voltage ( unless in a configuration like a voltage divider)

[verpies]

maybe... so it's more likely to reduce the current than voltage ( unless in a configuration like a voltage divider)

The forward voltage between the base and emitter will always be between 0.5V an 0.7V.   
Even if you apply 1000V at one end of the base resistor, the other end of this resistor (the end attached to the base) will have only 0.5V to 0.7V on it (measured to the emitter).  If you forcefully exceed this 0.7V voltage, by e.g. applying the 1000V directly to the base, then the transistor will blow up.

[verpies]

I'm not convinced that in my case, the toroid is saturating early on in the waveforms curving leading edge. If this were the case why is a heat sink called for both toroid and power transistor? Both me and Itsu can see this curve at low power levels with minimal heating of the transistor. I cannot see how the toroid could even get warm unless the flyback diode went OC. Can you see how the toroid might get very hot in this circuit configuration to warrant the use of high temperature Teflon covered wire and heat sink mounting?

Well, you know the drill:
First observe how rectangular the current waveform is when the transistor is loaded only with the 10Ω Load Resistor in the collector path.
If it is rectangular, then calculate the slope of the current waveform at the very beginning of the pulse when the transistor is loaded only with the W1 inductance, in series with the 0.1Ω CSR.
According to the table below, with unloaded secondary, your W1 self-inductance, calculated according to: L=V*dt/di, should be close to 88μH without saturation and >20 times less - with saturation.


Who         Turns   OD [mm]    ID [mm]    TH [mm]          L [μH]           μ_r       A_L [μH/N²]     Saturation @ [AmpTurns]
------------------------------------------------------------------------------------------------------------------------------------------------
Hoppy           6           11.0            5.0             4.0         88.000       3875          2.444                      ? ? ?
Hoppy         12           11.0            5.0             4.0       312.000       3435          2.167                      ? ? ?
Black_Bird   10             2.0            4.5             4.0           3.500           45          0.035                      ? ? ?
Black_Bird     8           10.0            5.0             5.0       220.000       4959          3.438                      ? ? ?
Black_Bird   16           10.0            5.0             5.0       870.000       4903          3.398                      ? ? ?
Itsu               6           16.6            9.4             6.9       173.000       6123          4.806                      0.133
Itsu             12           16.6            9.4             6.9       669.000       5920          4.646                      ? ? ?
Itsu               6             7.0            4.0             2.0         30.000       3723          0.833                      ? ? ?
Itsu             12             7.0            4.0             2.0       133.000       4126          0.924                      ? ? ?
Itsu               6           10.0            6.0             4.0         11.000         748          0.306                      ? ? ?
Itsu             12           10.0            6.0             4.0         77.000       1308          0.535                      ? ? ?
madsatbg     3           10.0            6.0             3.0           9.800       3553          1.089                      ? ? ?
madsatbg   10           10.0            6.0             3.0       104.500       3410          1.045                      ? ? ?
madsatbg     3           14.0            7.0             3.0         24.950       6666          2.772                      ? ? ?
madsatbg   10           14.0            7.0             3.0       236.300       5682          2.363                      ? ? ?

[itsu]

I tried the various suggested triggering schemes, but none really worked.
So i have just my red probe across the 1 Ohm csr and triggered on that signal.
I used the new setup where the flyback diode is outside the measurement circuit.

I measured the current through the 1 Ohm csr for the 3 toroids, and also measured the current across a 10 Ohm base resistor (this 10 Ohm is in series with the both MOSFET driver resistors 1 and 4.7 Ohm resp.).
The current through this 10 Ohm resistor was 1.2A when the collector voltage was 150V.

Seems that the 2 new little toroids saturate even earlier.
All 3 where measured with the 6 turn side only.
Repetition freq. was 4.6Khz, pulse width 765nS

Video: http://www.youtube.com/watch?v=Ohu1OsqqwxA&feature=youtu.be

Regards Itsu