Testing the transient response of PWM converters by LTspice

Рет қаралды 2,051

Ай бұрын

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Пікірлер: 32

@slazinger Ай бұрын

Marvellous video as always. I myself have expirience designing and testing this type of converters and I have always wondered why the step response wasn't really matching with the phase margin measurements. The more I learn about loop analysis, the more I find that in real applications there are a lot of nuances that affect the behaviour of the systems and most of the time is not easy or intuitive to draw conclusions.

@sambenyaakov Ай бұрын

Thank you very much for sharing you experience and thoughts.

@SMV1972 Ай бұрын

Какие же у Вас фундаментальные знания.! Вся силовая электроника для Вас как таблица умножения. И вы этим делитесь. Благодарю Вас!

@sambenyaakov Ай бұрын

большое спасибо

@SMV1972 Ай бұрын

@@sambenyaakov Здравствуйте! Не смог самостоятельно разобраться. Никак не получается получить график Боде для LC. Не могли бы Вы объяснить куда вводится параметр Table(0, 0, 10, 10) . Заранее спасибо

@sambenyaakov Ай бұрын

@@SMV1972 This belongs to the dependent voltage source E

@joet4348 Ай бұрын

Hi Sam, I just wanted to acknowledge how amazing it is to have your presentations available on KZfaq. I'm grateful that you take the time to share your experience and knowledge with us. You have so many videos covering topics of interest for me (especially in power electronics). I have some textbooks that I want to use for self study but I have struggled to find time to work through these massive books. I can get quality exposure to electronics through your videos to supplement the experience I pick up at work. I'd appreciate it if you continued to share videos with us for a long time to come.

@sambenyaakov Ай бұрын

Thanks for kind note. Comments like yours keep me going.

@Zetex2000 Ай бұрын

As always very interesting and helpful. Thanks! 😊

@sambenyaakov Ай бұрын

👍😊🙏

@ikocheratcr Ай бұрын

Looking at the current thru inductor after changing the feedback capacitor, I realized that a capacitor that loses its value can create a damage path that make some transistor pull more current and damage it. I think this is something you will never see a root locus plot, but shows an interesting chain of events for a catastrophic failure.

@sambenyaakov Ай бұрын

If you mean reduced capacitance you certainly can see this in the transfer function if you model the cap after change. But if you mean a partial short this is a different story.

@ikocheratcr Ай бұрын

@@sambenyaakov I meant no short. Capacitor change like issues that electrolytics present. Thanks for teaching us all. :) :)

@sambenyaakov Ай бұрын

@@ikocheratcr 👍

@tamaseduard5145 Ай бұрын

👍🙏❤️

@sambenyaakov Ай бұрын

Thanks

@Graham_Wideman Ай бұрын

Very nice examination! A minor point -- 18:42 "the switching frequency is about 30 kHz now (since it is a constant on time the frequency might change)". Yet the handwriting says fs ~= 300kHz. The waveforms show a main frequency around 27kHz (agreeing with the handwritten fc) with smaller waves (I assume the switching frequency) around 180kHz, it seems to me. The 180 kHz seems more likely a deviation from 300kHz than from 30kHz. So I believe the handwritten 300kHz is correct, not the voice 30kHz?

@sambenyaakov Ай бұрын

Yes, you are right, I meant 300kHz. You have a sharp perception and endurance, only about 20% of the viewers reach 18 minutes😊

@Graham_Wideman Ай бұрын

@@sambenyaakov Thanks for the reply! Since 100% of the presenter reached the end of the video, I feel it is my duty to watch the whole thing 🙂.

@sambenyaakov Ай бұрын

👍Hear, hear!

@vicentematricardi3596 Ай бұрын

❤❤❤❤❤👍👍👍👍

@sambenyaakov Ай бұрын

Wow. Thanks. I appreciate it.

@vicentematricardi3596 Ай бұрын

@@sambenyaakov Tengo un gran aprecio hacía su persona... 👍

@sambenyaakov Ай бұрын

@@vicentematricardi3596 🙏

@mtwieg24 22 күн бұрын

I'm curious if you've tried the new LTspice 24? Apparently its major new feature is the "FRA" which extracts bode plots from transient simulations. Haven't tried it myself, but thought it might be of interest to you.

@sambenyaakov 21 күн бұрын

Thanks. First time I hear about it. I guess it is a rebuttal to Qspice

@biswajit681 Ай бұрын

Hi sir could you please make a video on average modelling of peak current mode active clamp forward converter

@sambenyaakov Ай бұрын

Too specific. Will try.

@biswajit681 Ай бұрын

@@sambenyaakov Thanks sir .. actually there are all lot resources available on Flyback converter but not on Forward converter ...it's very hard to find out good resource on Forward converter

@raviselvans1963 Ай бұрын

Thanks a lot prof. I have one doubt why ppl are recommending gain margin should be above 12 db? What the role of gain margin?

@sambenyaakov Ай бұрын

Gain margin is another issue. I have a assumed that there is only one area in which the LG approaches 1. If at another frequency the LG approaches 1 it is altogether another story. Perhaps a video on that will be interesting😊

@biswajit681 10 күн бұрын

@@sambenyaakov sir could you please make video on the LG approaches 1 at different frequencies as you mentioned on above comments