Language: 
To browser these website, it's necessary to store cookies on your computer.
The cookies contain no personal information, they are required for program control.
  the storage of cookies while browsing this website, on Login and Register.

GDPR and DSGVO law

Storing Cookies (See : http://ec.europa.eu/ipg/basics/legal/cookies/index_en.htm ) help us to bring you our services at overunity.com . If you use this website and our services you declare yourself okay with using cookies .More Infos here:
https://overunity.com/5553/privacy-policy/
If you do not agree with storing cookies, please LEAVE this website now. From the 25th of May 2018, every existing user has to accept the GDPR agreement at first login. If a user is unwilling to accept the GDPR, he should email us and request to erase his account. Many thanks for your understanding

User Menu

Google Search

Custom Search

Author Topic: Chinese Oscillator and MOS FET Driver, Hardware experiment  (Read 28833 times)

Offline Jeg

  • Hero Member
  • *****
  • Posts: 1539
Re: Chinese Oscillator and MOS FET Driver, Hardware experiment
« Reply #15 on: December 05, 2020, 01:46:20 PM »
Packing the PVC core with magnetite composit would be much simpler then shaping that rectangular job right?

There its really not much to this build; The coils are household wire! What kind of advantage would there be in building a ferrite core with blocks? Permeability can be controlled with particulate ratio.

Yes this is true. Only the total ohmic resistance will change. I used ferrite rings for this task.

What is your opinion on the voltage across the 28T coil? Should it give a voltage level depending on the turns ratio, or it also depends on other factors due to the in series resonance?

Offline synchro1

  • Hero Member
  • *****
  • Posts: 4652
Re: Chinese Oscillator and MOS FET Driver, Hardware experiment
« Reply #16 on: December 05, 2020, 01:53:04 PM »
Yes this is true. Only the total ohmic resistance will change. I used ferrite rings for this task.

What is your opinion on the voltage across the 28T coil? Should it give a voltage level depending on the turns ratio, or it also depends on other factors due to the in series resonance?

That shift in voltage could be caused by incorrect grounding of your oscilloscope. How is the scope grounded?

Offline Jeg

  • Hero Member
  • *****
  • Posts: 1539
Re: Chinese Oscillator and MOS FET Driver, Hardware experiment
« Reply #17 on: December 05, 2020, 01:55:06 PM »
Yes it is grounded but now that you say it i will check again. My Rigol's probes are all grounded.

Ahh do you think it is because we have a zvs driver? The primaries are in a parallel tank circuit which gives rise to voltage. Perhaps that is the reason.

Offline synchro1

  • Hero Member
  • *****
  • Posts: 4652
Re: Chinese Oscillator and MOS FET Driver, Hardware experiment
« Reply #18 on: December 05, 2020, 02:04:40 PM »
Yes it is grounded but now that you say it i will check again. My Rigol's probes are all grounded.

Ahh do you think it is because we have a zvs driver? The primaries are in a parallel tank circuit which gives rise to voltage. Perhaps that is the reason.


If you are reading voltage off the 28T coil, that coil itself needs to be independently scope grounded to get an actual measurement.

Offline Jeg

  • Hero Member
  • *****
  • Posts: 1539
Re: Chinese Oscillator and MOS FET Driver, Hardware experiment
« Reply #19 on: December 05, 2020, 02:06:17 PM »

If you are reading voltage off the 28T coil, that coil needs to be grounded to get an actual measurement.

Yes i have connected one side of it to the negative of the pwr sup and also to the ground through the probe's alligator clip if this is what you mean.

Offline synchro1

  • Hero Member
  • *****
  • Posts: 4652
Re: Chinese Oscillator and MOS FET Driver, Hardware experiment
« Reply #20 on: December 05, 2020, 02:08:36 PM »
Yes i have connected one side of it to the negative of the pwr sup and also to the ground through the probe's alligator clip if this is what you mean.


Resonance must account for it. That kind of voltage is illusary.

Offline Jeg

  • Hero Member
  • *****
  • Posts: 1539
Re: Chinese Oscillator and MOS FET Driver, Hardware experiment
« Reply #21 on: December 05, 2020, 02:13:28 PM »

Resonance must account for it.

I'll change resonant point to lower values than 110Khz, to see its reaction. If i could step up the voltage across the 28T without raising the input voltage or the turns of the secondary, i might reach the result of the Chineese in terms of performance. Across 28T i measure 400V peak to peak, but Chineese's device might be well more than this.

Offline synchro1

  • Hero Member
  • *****
  • Posts: 4652
Re: Chinese Oscillator and MOS FET Driver, Hardware experiment
« Reply #22 on: December 05, 2020, 02:16:47 PM »
I'll change resonant point to lower values than 110Khz, to see its reaction. If i could step up the voltage across the 28T without raising the input voltage or the turns of the secondary, i might reach the result of the Chineese in terms of performance. Across 28T i measure 400V peak to peak, but Chineese's device might be well more than this.


The capacitor tuning for high "Q" is where you get the advantage. Do you have a tuner connected to your capacitor?

Offline Jeg

  • Hero Member
  • *****
  • Posts: 1539
Re: Chinese Oscillator and MOS FET Driver, Hardware experiment
« Reply #23 on: December 05, 2020, 02:19:56 PM »

The capacitor tuning for high "Q" is where you get the advantage.

Nice point!!! I just don't know how to increase the Q of the primary side when using just 5T per primary. I'll make some calcs more to see. Perhaps his ferite core is more suitable than mine's. I use just a simple yoke core.

Offline synchro1

  • Hero Member
  • *****
  • Posts: 4652
Re: Chinese Oscillator and MOS FET Driver, Hardware experiment
« Reply #24 on: December 05, 2020, 02:21:48 PM »
Nice point!!! I just don't know how to increase the Q of the primary side when using just 5T per primary. I'll make some calcs more to see. Perhaps his ferite core is more suitable than mine's. I use just a simple yoke core.


You need a tuner cap! There's an 8000 volt .022uf capacitor in the schematic. That's the trimmer cap! You got it to ring, but any further resonant voltage rise would be a consequence of the trimmer capacitor adjustment for "Q" in micro farads. 

Offline Jeg

  • Hero Member
  • *****
  • Posts: 1539
Re: Chinese Oscillator and MOS FET Driver, Hardware experiment
« Reply #25 on: December 05, 2020, 02:33:02 PM »

You need a tuner!

Thanks, i'll think more about it. The other solution is to make a peak shorting across the 28T to raise its voltage as much as i can. For now i am just trying to go as per Chineese circuit. Even if there is a fat chance that the Chineese hides something in his contraption like a HV converter module. It is not possible with the given circuit to reach 200V across a 2KW induction cook like the Chineese shows.

Offline Jeg

  • Hero Member
  • *****
  • Posts: 1539
Re: Chinese Oscillator and MOS FET Driver, Hardware experiment
« Reply #26 on: December 05, 2020, 02:37:04 PM »

You need a tuner cap! There's an 8000 volt .022uf capacitor in the schematic.

Exactly. This is an indication that we have HV running inside his tank circuit. I can't reach a higher than 400V pk-pk. I also use an input choke to my ZVS driver. The Chineese doesn't.

Offline synchro1

  • Hero Member
  • *****
  • Posts: 4652
Re: Chinese Oscillator and MOS FET Driver, Hardware experiment
« Reply #27 on: December 05, 2020, 02:49:17 PM »
The "Gimmick" is that the designer matched a household wire coil to a resonant capacitor and tuner all in correct proportion to deliver a very high "Q"!

The high 8000 voltage rating does not prevent the trimmer from working in the lower voltage ranges; However, when tuning for "Q", these voltages develop between the capacitor plates. The trimmer is nothing like an ordinary butterfly capacitor.


The coil turns and primary capacitor are matched sufficiently to produce a basic resonance that the fine tuner capacitor can operate on. Ordinary variable capacitors will burn out too soon.

Offline color

  • Hero Member
  • *****
  • Posts: 2264
Re: Chinese Oscillator and MOS FET Driver, Hardware experiment
« Reply #28 on: December 05, 2020, 02:50:54 PM »
Thanks, i'll think more about it. The other solution is to make a peak shorting across the 28T to raise its voltage as much as i can. For now i am just trying to go as per Chineese circuit. Even if there is a fat chance that the Chineese hides something in his contraption like a HV converter module. It is not possible with the given circuit to reach 200V across a 2KW induction cook like the Chineese shows.

Exactly. This is an indication that we have HV running inside his tank circuit. I can't reach a higher than 400V pk-pk. I also use an input choke to my ZVS driver. The Chineese doesn't.

================

My dad learned a lot from you.
Even small Yoke-transformers have little effect on the output.
Note please.

Offline NickZ

  • Hero Member
  • *****
  • Posts: 5150
Re: Chinese Oscillator and MOS FET Driver, Hardware experiment
« Reply #29 on: December 05, 2020, 02:52:18 PM »
   Jeg:   Do you guys have a picture or video of what you are trying to replicate? Or, your version of it?
   Is this circuit being discussed here supposed to be  OU, or self runner?
    NickZ