#75🚀 EVAL 25 kW Dual Active Brigde

SuperPowers for Electrical Engineers 🦸🏻‍♂️🦸🏼‍♀️

👋 Hello, friends! Dr. Molina here 👨‍🔧

Welcome to Dr.Molina Newsletter, where I break down Magnetic design for you every week, in 4 minutes the time needed.

It’s been a Good show. APEC always brings interesting conversations and learnings. I have listened to discussions about sustainability, electrification, how to produce electric cars with smaller carbon footprint, and of course, power electronics. However, It’s the technical time!

EVAL 25 kW Dual Active Brigde

If you are working for EV chargers, ST has developed a 25 kW Dual Active Bridge with a Transformer designed with Frenetic Online. During APEC, they had a demostration board which generated a lot of interest. In the link, you can find all the information. For the transformer, we can support you with samples (under proposal request).

Flyback coupled with the CMC

This APEC was amazing and probably thanks to its chairman Pradeep Shenoy. He also was one of the authors of an education seminar from TI about typical mistakes in power electronics. I have chosen a small tip they have shared which I think is interesting for you.

For laptops or phone chargers, power density is critical. The most common topology for these cases below 100W is Flyback. They need to comply with EMI restrictions, and in most of cases, there is an EMI filter based on inductors and capacitors. There is a CM choke, which is basically doing a lot of work.

However, what happens in some designs?

The Flyback magnetic is so noisy that can generate a lot of radiated noise and couple with the CM choke. If this happens, the noise is not attenuated, and we get crazy.

The solution proposed by TI is to play with the physical disposition of the components. After all, there is physical radiation through the air and is due to the magnetic field. If we change the direction of the magnetic field lines, we could avoid the coupling between the flyback and the CM.

They propose to use a flux band connected to the primary ground. Every engineer will have their own solutions, but if you avoid them from the very beginning, you will save a lot of headaches.

References

[1] “Common Mistakes in Power Supply Designs”, Sheng-Yang Yu, Fei Yang, Brian King and Pradeep Shenoy. Education Seminars S09, APEC 2023, Orlando Florida

News About Frenetic

1. Webinar about LLC Transformer Design- Registration Link

2. During APEC, we presented the future of our Library of off-the-shelf (OTS) magnetics, which we are working on it. We will do a webinar in April about it.

3. We have a new Home and some new features which really got great feedback during APEC

   1. Custom Cores

   2. Custom Bobins

   3. A Library of Bobins

If you missed….some of the most widely read articles in the Dr.Molina Magnetics Newsletter:

#58🚀 How to design an Inductor

#54 🚀 How do engineers learn Power Electronics?

#51 🚀 Full Bridge TX PQ40/40 Leakage Inductance Game

#34 🚀 Dual Active Bridge 3,3kW 380/54V

#8 🚀 How to design a 600W Power Supply Full Bridge Transformer, Product Design and Community