Water Sparkplug

[Kinetix]

Hello, guys.
In order to dissolve The Fried Inverter Club, I have a sugestion to make. It's about a charge pump to be used instead of inverter. It does the same job, and it is cheaper to make.
I have just finished one and made some bench tests. It worked well so far. Nothing got significantly hot. I have set it to make 400V at idle and simulated points with a signal generator, as the engine would run at 6000rpm. At that speed, the voltage across the discharge capacitor lowerred a bit, to 350V. The plasma spark generated is about 1.5mm thick (the regular hv spark is 0.5mm thick).
In order to obtain bigger sparks, one could increase the value of the discharge capacitor (e.g: 2.2uF, 4.7uf, etc). In that case the voltage could go down a little, but it should remain enough to make a strong discharge.
I used a 25 string of 1N4007 in tests and didn't get hot.
Hope in a day or two I will be able to mount it on my car.

All the best!

[Ansis Freimanis]

Hi, Kinetix!

I want to say something.
Your circuit is OK, but I see one problem...
Your "fine adjustments" of output voltage, in my understanding is not "wise".
If You take 10K adjustable (audio) resistor and put it between pin 3 and R3 (Your R3 must be about 560 Ohm) in "split" circuit (like in amplifier- audio volume potentiometer) and remove T3; D5; RV1; R5- that makes Your circuit more "flexible" and stable( because Your RV1 is working with High potential and it can start burn out, after some period of time). If You make this more simpler circuit with 10K adjustable resistor- You can start opening Your Darlington from minimal base currents and output voltage- is regulating from 0 Volts to maximal now.
P.S. In Greg circuit, his output is only about 150 Volts DC (on Your C5).
Be, happy!

[Chris31]

I want to say something.
Your circuit is OK, but I see one problem...
Your "fine adjustments" of output voltage, in my understanding is not "wise".
If You take 10K adjustable (audio) resistor and put it between pin 3 and R3 (Your R3 must be about 560 Ohm) in "split" circuit (like in amplifier- audio volume potentiometer) and remove T3; D5; RV1; R5- that makes Your circuit more "flexible" and stable( because Your RV1 is working with High potential and it can start burn out, after some period of time). If You make this more simpler circuit with 10K adjustable resistor- You can start opening Your Darlington from minimal base currents and output voltage- is regulating from 0 Volts to maximal now.
P.S. In Greg circuit, his output is only about 150 Volts DC (on Your C5).
Be, happy!

The circuit is using feedback to regulate the output voltage as set by the variable resistor.

I must say, it is possible to use the reset pin of the timer to shut it down rather than T3 "shorting" the supply of the timer to ground.

Reset pin is active low on 555, on reset Q is kept low and therefore turning off T1 and T2 until the output voltage has fallen back to the desired set output.

[gmeast]

charge pump

Hello, guys.
In order to dissolve The Fried Inverter Club, I have a sugestion to make. It's about a charge pump to be used instead of inverter. It does the same job, and it is cheaper to make.
I have just finished one and made some bench tests. It worked well so far. Nothing got significantly hot. I have set it to make 400V at idle and simulated points with a signal generator, as the engine would run at 6000rpm. At that speed, the voltage across the discharge capacitor lowerred a bit, to 350V. The plasma spark generated is about 1.5mm thick (the regular hv spark is 0.5mm thick).
In order to obtain bigger sparks, one could increase the value of the discharge capacitor (e.g: 2.2uF, 4.7uf, etc). In that case the voltage could go down a little, but it should remain enough to make a strong discharge.
I used a 25 string of 1N4007 in tests and didn't get hot.
Hope in a day or two I will be able to mount it on my car.

All the best!

Hi Kinetix,

I have been running my VexUs circuit on a simple two transistor oscillator / inverter for some weeks now ... I posted a vid to the effect and a vid also of just the oscillator. It's the one I posted a couple of weeks ago on overunity.com and I think here too. I'm using only two of the four showm in mine. This old design is not efficient until it is drawing power, but it is bullet proof. You have to select caps to get the correct LR/LC/RC relationships for the proper frequency ... it can be a pain, but once set it's "mmmmmmm" good.

We're trying to keep any CMOS out of it.

Peace,

Greg

[gmeast]

4 transistors

Hi Mike,

Today I added two more transistors to my two on the bench test circuit. I have a 115VAC x 10VAC transformer with a center tap on the secondary so I wired it in. The circuit transistors get a little warm just sitting there but when you start to draw power from it they cool down @#$%&%# ? But that's fine. With just a FWB I get a solid 250 VDC and it sags NOT upon firing the distributor & plug at 2400 RPM ... that's 160 cycles per second !

That's a gain of 50 VDC over what I have now. Thought I'd share.

Peace,

Greg

[jstadwater]

Hey Greg,

That's definitely good news, AGAIN! I have evrything ordered by 2nd day air, except a 24VA transformer. I'm having a little trouble finding one with the right specs. I decided I wanted a new one instead of used, (the one I sent you stats on was on E-bay, used). I did order some various sizes on the parts, so I can play around some with the circuit. Hopefully tomorrow I can nail down a transformer. I also got my laptop back functional today, it got a cold from the internet. I will be testing tomorrow how far I can lean out this 350 Chevy! I'll post results as I get them. Thanks again for everything, later.......................Mike

[lapperl]

Hey Greg,

That's definitely good news, AGAIN! I have evrything ordered by 2nd day air, except a 24VA transformer. I'm having a little trouble finding one with the right specs. I decided I wanted a new one instead of used, (the one I sent you stats on was on E-bay, used). I did order some various sizes on the parts, so I can play around some with the circuit. Hopefully tomorrow I can nail down a transformer. I also got my laptop back functional today, it got a cold from the internet. I will be testing tomorrow how far I can lean out this 350 Chevy! I'll post results as I get them. Thanks again for everything, later.......................Mike

@jstadwater;

I wouldn't go with the 24 volt transformer. It does exactly what the diagram says that Greg posted; it produces 90 volts at 60 hz. The 18 volt also does what it states but at around 120 hz with a load.

I just built the circuit over the weekend, but have not had a chance to post until tonight. It works great!

I purchased both the 24vdc 1 amp and the 18vdc 1 amp with center taps to test them both and the 18vdc produces higher voltage. I'm no electronics expert, but from the results that Greg posted last week using the 10vdc transformer, he appears to be getting higher voltage. With his most recent mod of adding the other two transistors, he's getting even more. I could be wrong, but the lower voltage tranny's appear to produce higher voltage.

The transistors in my circuit do not appear to get that hot. At least nothing to be worried about. Although the resistors do get very warm. I used a meat thermometer and they got up to 140 degrees Fahrenheit, but that is still within the allowable limits on the spec sheet which states -60 Celsius to + 275 Celsius (512 Fahrenheit). A small fan cools them right down though.

Just my two cents.

@Greg,

Please correct me if I'm wrong in any way. Like I said, not an electronics engineer.



LapperL

[gmeast]

transformers

@jstadwater;

I wouldn't go with the 24 volt transformer. It does exactly what the diagram says that Greg posted; it produces 90 volts at 60 hz. The 18 volt also does what it states but at around 120 hz with a load.

I just built the circuit over the weekend, but have not had a chance to post until tonight. It works great!

I purchased both the 24vdc 1 amp and the 18vdc 1 amp with center taps to test them both and the 18vdc produces higher voltage. I'm no electronics expert, but from the results that Greg posted last week using the 10vdc transformer, he appears to be getting higher voltage. With his most recent mod of adding the other two transistors, he's getting even more. I could be wrong, but the lower voltage tranny's appear to produce higher voltage.

The transistors in my circuit do not appear to get that hot. At least nothing to be worried about. Although the resistors do get very warm. I used a meat thermometer and they got up to 140 degrees Fahrenheit, but that is still within the allowable limits on the spec sheet which states -60 Celsius to + 275 Celsius (512 Fahrenheit). A small fan cools them right down though.

Just my two cents.

@Greg,

Please correct me if I'm wrong in any way. Like I said, not an electronics engineer.



LapperL

Hi,

Yes you are correct. The transformers are normally step down transformers if you put 115VAC on what is labeled as the 'primary'. The secondary usually has the capability of dual voltage like (+ 12 VAC and - 12 VAC using the center tap) as one voltage(s) or 24 VAC if you ignore the center tap. Or with dual secondary output no center tap you can have 12 VAC at twice the current (parallel) or 24 VAC at half the current (series) wired.

But ... in this, you run it in reverse. Simply ... instead of 115 VAC to say 10 VAC it is 10 VAC to 115 VAC. 115 VAC to 3 VAC turned around would be 3 VAC to 115 VAC as a step up transformer. But this is only for illustration ... the numbers only kind of work that way because of power ratings, efficiencies, etc. What's nice is these things also double as isolation transformers.

Thanks lapperl for chiming in. Peace,

Greg

[jstadwater]

OK, so I'll just order a couple 18V and a couple 10V transformers. Then I should be covered, right? Let's not forget though, I am working on a 8 cylinder instead of 4. I have to have twice the firing speed as Greg to be able to only use one unit. Otherwise I will just use two units and be done with it. I'll add in either a voltage doubler or tripler, depending on my final available output voltage. Thanks for the input, later..........................Mike

[Kinetix]

Hello, everybody.
Ansis Freimanis, you are right. There are many (maybe even better) ways to command the 555. I think your's is a good one.
I have just used a setup that I thougt it would do. And... it did.
In fact, there is a most simple way to reduce the output voltage: add a few more turns to primary winding (or reduce the secondary winding by a few tens of turns and you're done. And it would not need any feedback regulation.
I used a transformer that I have allready wound prior to this, for another schematic. Anyway, the idea is to not exceed the capacitors voltage rated value.
On the RV1 we have a calculated voltage of only 3.17V, and the current that passes through it is only 1.6mA. It shouldn't burn too fast.
Greg, I have been waiting for your schematic for a few days. Thank you for posting it. I think it is a push-pull setup and should have a good eficiency. In fact you can calculate this after measuring the input energy consumption versus the output.

With the values on the schematic I posted, it manages to maintain 350V on discharge capacitor (C5) at about 6000rpm (simulated).
More information after mounting it on my car and runtest it.

Best wishes!

[Ansis Freimanis]

Hi, Kinetix!

I know- HV is always - "end of the road". Energy is much higher in HV if we compare it with 12-14V. My understanding is "no feedbacks" in HV area- reason is- if your circuit start burn out process there start another processes which are make scheme not stable and you don’t understand- why? If you make your scheme simple as possible- You’ll be the winner! Simplicity is the key to success.

[Ansis Freimanis]

Hi, Greg!

I think Your STORAGE CUP (VexUs) must be with higher capacitance as possible. Why? Because this capacity is "stabilization" of secondary voltage. If You take 1000uF (instead, yours 470uF) the circuit must work with less heat. Reason is lowering the primary current. In the oscilloscope it will be much less discharge process on STORAGE CUP.
P.S. I am not an Englishman (I try to explain- how I can).
Thanks.

[gmeast]

storage Cap

I think Your STORAGE CUP (VexUs) must be with higher capacitance as possible. Why? Because this capacity is "stabilization" of secondary voltage. If You take 1000uF (instead, yours 470uF) the circuit must work with less heat. Reason is lowering the primary current. In the oscilloscope it will be much less discharge process on STORAGE CUP.
P.S. I am not an Englishman (I try to explain- how I can).
Thanks.

Hi Ansis,

At present my Storage Cap is at 33uF in the oscillator configuration and my CDI Cap is at 4uF. But you're correct in that with a bigger Storage Cap it is more steady as a DC supply to the CDI Cap. I figured 8 - 10 X the CDI Cap value was sufficient. On an oscilloscope trace the charge curve becomes 'smooth' and classic with only 33uF.

You're also very correct in pointing out the lower peak current on the transformer primary because current flows mostly during the full 'on' time of the oscillator and less during turn-on transition (rising edge). Also the current on the primary is a multiple of (many times) the current flowing from the Storage Cap to the CDI Cap and to the spark plug in the end.

Yes ... very good indeed !

Peace,

Greg

[Chris31]

Hello, everybody.
Ansis Freimanis, you are right. There are many (maybe even better) ways to command the 555. I think your's is a good one.

Soft switching the power transistor by decreasing the base current would decrease the efficiency of the circuit and you will find the transistor overheats.

Anyway choice is yours, if it work for you so

[Ansis Freimanis]

Hi, Chris31!

Absolutely- NO PROBLEMS. You must working with Sine wave form- no 555 timers!!!. I can say- it is not possible to overheat, because- (if You working with Darlington with high current gain, and if You working with MOSFET`s) You start with 0 Volts. Your secondary voltage is 0 too. After You start open Your Darlington(12000 gain of current, or power MOSFET)- the secondary voltage start go up, but current (it is very important) start go from 0 Amps too. It’s absolutely linear process!!! That is AMPLIFICATION process.
P.S. If You work with oscilators- like Greg one, then you MUST TAKE SELF OSCILATOR with sine wave form too- in simple explanation- NO MULTIVIBRATORS WITH CAPACITY IN TIME CORECTION CIRCUITS only feedback from primary!!!
Thank, You!