What is exactly the phase margin frequency? this omega pm1 you calculate in the minute 4:30, I thought it was the following (i'll try explain myself as well as i can), if you ignore the frequency response and you do a root locus analyisis, when you find out the "wanted poles" that makes your system meet the design requirements, these have a real part and an imaginary part, well I thought this imaginary part was given by what you call phase margin frequency, but now with this video I don't quite grasp the concept of this, I'd appreciate very much if you could help me understand it. PD: YOUR VIDEOS ARE AMAZIN, everything is very clear and you make it easier to understand PLUS you've taken the time to do it in MATLAB, which really makes this video TOP CLASS, I appreciate you for takin time to make these amazing videos to help strangers :)

@CanBijles

10 ай бұрын

Hi, thanks for your message. Great to know you like the video! 1. Phase margin frequency is the frequency where the required phase margin is achieved. This is determined by looking at the loop gain = 1, so at what frequency is the loop gain equal to 1. 2. The imaginary part of the design point (where the dominant poles are) is not the phase margin frequency. The following link explains graphically what the gain margin, phase margin, gain margin frequency, and phase margin frequency is. You can use the command margin(sys) in MATLAB with sys the loop gain transfer function to show these data. nl.mathworks.com/help/control/ref/dynamicsystem.margin.html Let me know if this was helpful.

@user-jc9kn4uy2u

10 ай бұрын

@@CanBijles It was really helpful, thank you very much !!

@CanBijles

10 ай бұрын

​@@user-jc9kn4uy2uYou're welcome!

dear professor, i am trying to learn controller design for power converters. for the power converters generally we consider gain margin parameter while designing a controller. in your video series i have seen that you did not mention about gain margin. as far as i know gain margin has an important role for transient responses such as line or load transients of power converters. could you please share your ideas about this and explain why you did not mention gain margin while designing pid controller?

@CanBijles

Ай бұрын

Thanks for your message. This is a valid and good question. Indeed, for the stability analysis, we should check both the gain margin and phase margin. In control theory, we also look at the modulus margin, which is actually a better measure how safe we are from the unstable point in the Nyquist plot. Usually (more often, but not always), the phase margin is somewhat more important than gain margin. If the phase margin is sufficient, than the gain margin is probably sufficient too, but of course there is no guarantee. In the videos I discussed about compensator design for buck converter, the gain margin was already large. In the links shown below, they discuss transient response of power converter and the discussion is also based on phase margin only. I do not claim you should only look at phase margin for power converters, but I do not know how strict and important the gain margin is for power converters. Maybe you have a good reference about it, love to read it. www.ti.com/lit/an/snoa507/snoa507.pdf?ts=1717893510339 pdfserv.maximintegrated.com/en/an/AN3453.pdf

@sahinbozkurt886

Ай бұрын

@@CanBijles çok teşekkür ederim hocam. Benim için oldukça anlaşılır bir cevap verdiniz. İyi çalışmalar dilerim.

@CanBijles

Ай бұрын

@@sahinbozkurt886 Rica ederim, memnun oldum. İyi çalışmalar.

Спасибо Вам огромное за прекрасное видео. Оно реально поможет решать практические задачи Я пытался сам просчитать частоту при 117 и она получилоась 2,94 rad/s. Если вам не сложно, не могли бы вы подсказать код Матлаб для правильного вычисления частоты?

@CanBijles

3 ай бұрын

Thanks for your message. I will share the MATLAB script of this problem as soon as possible in the video description and also check the calculations for the phase and frequency.

@SMV1972

3 ай бұрын

@@CanBijles благодарю Вас!

@CanBijles

3 ай бұрын

​@@SMV1972You're welcome.

@CanBijles

3 ай бұрын

​@@SMV1972 Here is the MATLAB script of this example: drive.google.com/file/d/13GDBFPsFWNiJLI_Nci44j3VWtqVvS5gO

Excellent video, but there is something I didn't understand. What is the step by step to obtain ωpm, is there a link or content to review. Because as far as I understand, that equation of arctangents equal to the phase margin has no possible solution.

@CanBijles

2 ай бұрын

Thanks for your message. Great to know that you liked the video! You can solve a equation using a graphing calculator or online equation solver like www.wolframalpha.com/calculators/equation-solver-calculator

@ControlAutomatico2020

2 ай бұрын

@@CanBijles I was trying to avoid that, but thanks fot the advice. Maybe Newton-Raphson can solve that.

@CanBijles

2 ай бұрын

@@ControlAutomatico2020 It is a nonlinear equation, so you can try to approximate it using numerical methods, but this will be tedious and not always easy to solve. But worth practicing 👍

How come you used a 2nd order formula to calculate the 3rd order dumping ratio?

@CanBijles

3 ай бұрын

Damping ratio formula is only valid for a second-order system without zeros. So it is approximating any other second-order system with zeros or a higher order system.

Kindly show in Matlab window

@CanBijles

10 ай бұрын

I will try to upload the files and show them in the coming videos. You can try this self in MATLAB too.

@CanBijles

3 ай бұрын

Here is the MATLAB script of this example: drive.google.com/file/d/13GDBFPsFWNiJLI_Nci44j3VWtqVvS5gO