#37 🚀 L=16 uH AC Inductor Design with Ansys - Accuracy Analysis
SuperPowers for Electrical Engineers
👋 Hello Supergineers! Dr. Molina here! 👨🔧
During my professional career, I have designed magnetics using mainly Pexprt and Maxwell from Ansys, because Pexprt was developed in the laboratory UPM-CEI.
I know very well the software and actually, at Frenetic we own licenses of Pexprt and Maxwell, that we use for generating tests and data for our Artificial Intelligence models (as we explain in our Training course of Magnetics).
This software are great. Probably COMSOL is also a good tool for FEM simulations, but without any design tool like Pexprt.
Simplis is also including in their circuit simulator the magnetic stimulation but without design generation.
The main advantage we added to Frenetic is the possibility of having the hardware of your designs in a few weeks and this idea created a lot of questions in users. Especially related to accuracy. The accuracy of our models is our day a day work and AI is helping a lot.
I haven´t asked Ansys, Orcad, Comsol, or Matlab for the accuracy of their models. However, I found it interesting to test the tools and share the results. Therefore, here we go!
Accuracy of Simulation tools
I have bad news. In the electromagnetic world, there are some models which are not well solved yet and the accuracy is limited so far. However, we have seen huge improvements in applying AI for solving specific models, like Llk, where we are reaching 90% of accuracy in some areas.
Inductor design
Today I will design and test an inductor using Pexprt and Maxwell 3D.
I have taken an AC current inductor as an example with the following specs:
L= 16,5 uH
fsw= 100 kHz
Irms= 14,15 A
I asked Pexprt for design ideas. Here are the proposals:
The first suggestion is a PM64, probably the biggest core available. As a recommendation, at Pexprt you need to select the cores you want to use, otherwise, he will bring you the biggest one.
I played with my personal criteria selecting a smaller core and litz wire. With the following details:
Core: PQ35
Number of turns: 13 x 3 parallels
Litz wire 375 x 0.05
The result in terms of losses and temperature for this design provided by Pexprt was 3,75 W and 57 ºC of temperature, which was acceptable for moving to the hardware stage.
Then I asked for a FEM model to Maxwell 2D and recalculate the losses, the result is very similar 55,3 ºC.
After building the component, I moved to the lab to test it.
This is what I measured when I applied the same current after building the component. I measured 107,8 ºC at the hottest point. In any case, the component temperature was stable.
Nevertheless, There is a 50ºC difference.
A license of Maxwell could be in the range of 50-150 k€ depending on the packages you get (plus the annual maintenance). No hardware. No design support.
And you know what? I think they have a great product. More than 20 years of helping engineers in very different areas.
We will continue using Maxwell for a lot of years for creating a database of simulations.
I will continue doing this exercise, as well as sharing our results, even when they are not good (In APEC 2022 I explained how bad our parasitic capacitance model😢 ).
Every SuperHero has their kryptonite and trying to discredit others is just proof of EGO.
A lot of engineers try to demonstrate how smart they are, trying to criticize others, but I’m afraid those engineers won´t be remembered by exposing their EGO.
You will be remembered for the products you put in the world, cars, audio amplifiers, lighting, TVs, and satellites.
As soon as you start working as the best engineers in the world, as soon your career will take off and you will be able to say to your kids:
Your dad designed part of thar space rocket 🦸🏻♂️.
HIGH-FREQUENCY MAGNETIC TRAINING - LAST DAY OF DISCOUNT
Tomorrow we will start with the second batch of our Training. As a Newsletter reader you can get special conditions: a 25% discount 😱 using the coupon NL25.
All the info about the Training Program is here.
Only Valid until TODAY.
If you want to get SuperPowers in power electronics, join our training.
Some of the instructors are:
Lucas Nicieza
Bob White
Alfonso Martinez
Marcos Luna
Sotiris
Top Editions
These are the most popular editions:
#8 🚀 How to design a 600W Power Supply Full Bridge Transformer, Product Design, and Community
#34 🚀 Dual Active Bridge 3,3kW 380/54V
#16 🚀 Design a 65 W Active Clamp Flyback Magnetic
#27 🚀 Where are the best Power Electronics engineers coming from?