@@sambenyaakov oh no, i thank you! About these ideas, some radioamateurs tested many years ago, two torroids put together, in an "8", cc on separate branches, rf on common branches, just like in the application you presented, but it lacked the air gap. It was said it liniarizes a bit the behaviour. I do not know how it works, but in that form is an old idea. With the air gap, neat! Btw, if i want to build an oscillator, should i use with air gap or not?
@@SergiuCosminViorel For just an oscillator you don't need a gap, But if it is part of a power conversion system you certainly need a gap to handle the power
@@sambenyaakov Am not completely regularly formed into a competent engineer, so to speak. Am an engineer, however not all lessons learnt. Is this about power density, power per volume of magnetic material, in the assumption that the oscillator uses low power, or is it about some other aspects. And if i have high power in the oscillator, maybe i need air gap?
I've thought about this concept countless times and always wondered how well it might work out. It's very gratifying to see this study and the idea actually being materialised. My motivation on this is in the entirely opposite direction and pursuing different ends. I was interested in audio transformers and not switching supplies. The question was whether a push-pull double C core output power transformer, with a minimum or zero air gap could be used for a single output device duty, where one would normally employ a single device biased with dc current that would flow through the core. The aim of course was to thus obtain maximum permeability by virtue of having minimal air gap and thus be able to use some core materials that would not normally be used with any dc current in the windings. Using a push-pull transformer in this way would result in the core saturating horribly. Winding window optimisation restrictions aside, I wondered how well having two compensating dc currents applied independently to each outer leg of the core would work (rather than the same current being applied to both legs as is the case here). The problem was, how would the two currents sum up in the central core so as to: a) counteract the amplifying device's bias current that would be applied to the winding on the central leg of the core and simultaneously b) ensure that neither of the C sections of the core would saturate. A ferrite core's manufacturing tolerances would I imagine be much much lower than a double C core's. Thus, where a single dc current suffices in a ferrite core, I would think two dc currents be necessary in a double C core on account of the two C sections having slightly different characteristics due to manufacturing tolerances. As far from a practical and economical application of this concept as possible I should think but a nagging question nevertheless.
Thx for the nice explanation. I think the core concepts were also applied in magnetic amplifier. If I remember right there is also a post regulator in pc smps which uses the concept of controllable inductance. Very nice 👍 Best regards and looking forward to your next presentation
Interesting concept that I tried to propose for a different application. The weaknesses are in the bias. The energy needed to "saturate " the core is basically wasted (unless a recirculation converter is designed), and the mu_r/i_bias is strongly dependent on uncontrollable factors (I.e. temperature )
Very interesting. I made an LC oscillator based on this when I was a teenager in an attempt to create a low distortion audio oscillator. But it was a disappointing exercise as the distortion was too high and my knowledge at the time was very limited.
I knew about all these, separate aspects, but never thought about putting it together. Very smart!
Thanks
@@sambenyaakov oh no, i thank you!
About these ideas, some radioamateurs tested many years ago, two torroids put together, in an "8", cc on separate branches, rf on common branches, just like in the application you presented, but it lacked the air gap. It was said it liniarizes a bit the behaviour. I do not know how it works, but in that form is an old idea. With the air gap, neat!
Btw, if i want to build an oscillator, should i use with air gap or not?
@@SergiuCosminViorel For just an oscillator you don't need a gap, But if it is part of a power conversion system you certainly need a gap to handle the power
@@sambenyaakov Am not completely regularly formed into a competent engineer, so to speak. Am an engineer, however not all lessons learnt.
Is this about power density, power per volume of magnetic material, in the assumption that the oscillator uses low power, or is it about some other aspects.
And if i have high power in the oscillator, maybe i need air gap?
@@SergiuCosminViorel is for the last sentence
Excellent and informative presentation 🤞🙏🙏
Thanks
Thank you for this video!
Thanks
I've thought about this concept countless times and always wondered how well it might work out. It's very gratifying to see this study and the idea actually being materialised.
My motivation on this is in the entirely opposite direction and pursuing different ends. I was interested in audio transformers and not switching supplies. The question was whether a push-pull double C core output power transformer, with a minimum or zero air gap could be used for a single output device duty, where one would normally employ a single device biased with dc current that would flow through the core. The aim of course was to thus obtain maximum permeability by virtue of having minimal air gap and thus be able to use some core materials that would not normally be used with any dc current in the windings.
Using a push-pull transformer in this way would result in the core saturating horribly.
Winding window optimisation restrictions aside, I wondered how well having two compensating dc currents applied independently to each outer leg of the core would work (rather than the same current being applied to both legs as is the case here). The problem was, how would the two currents sum up in the central core so as to:
a) counteract the amplifying device's bias current that would be applied to the winding on the central leg of the core and simultaneously
b) ensure that neither of the C sections of the core would saturate.
A ferrite core's manufacturing tolerances would I imagine be much much lower than a double C core's. Thus, where a single dc current suffices in a ferrite core, I would think two dc currents be necessary in a double C core on account of the two C sections having slightly different characteristics due to manufacturing tolerances.
As far from a practical and economical application of this concept as possible I should think but a nagging question nevertheless.
Thank you very much for sharing your thoughts and observations.
Thx for the nice explanation.
I think the core concepts were also applied in magnetic amplifier. If I remember right there is also a post regulator in pc smps which uses the concept of controllable inductance.
Very nice 👍
Best regards and looking forward to your next presentation
Thanks for note. Yes, the fundamentals are the same s the mag mp but the these are different construction and applications (e.g. LF versus HF).
Priceless.
Thanks Hamid
Thanks Hamid
Interesting concept that I tried to propose for a different application. The weaknesses are in the bias. The energy needed to "saturate " the core is basically wasted (unless a recirculation converter is designed), and the mu_r/i_bias is strongly dependent on uncontrollable factors (I.e. temperature )
Indeed, one has to check is the gain is higher than the loss.
Very interesting. I made an LC oscillator based on this when I was a teenager in an attempt to create a low distortion audio oscillator. But it was a disappointing exercise as the distortion was too high and my knowledge at the time was very limited.
Thanks for comment. Neve too late😊
👍🙏❤
😊👍🙏