Hello, Sotiris here! 👋

 🚀Today we’ll talk about time delays when you’re debugging a design. Also, we take a break from PFCs, and we’ll focus on Phase Shifted Full Bridge (PSFB) transformer design. Plus there's a special gift 🎁 at the end for our Newsletter subscribers. 

✅   What’s our goal in Frenetic? Speed up the magnetics design process from weeks to hours!    🚀 😎 🚀 That’s what you should expect from our online platform, anyway❗

I know from experience, that when it comes debugging and testing pcbs and circuits, the biggest hurdle an engineer faces is time delays 😰.

👉 So you’ve busted you head again the wall and came up with a solution, whether that’s a “patch” pcb, or some part numbers changed, or you’ve burnt some components during testing and you need to order stuff, from around the globe 🌎. Say goodbye 👋 to your time management skills now, because you’re dependent on shipping time, or a pcb factory etc.

🔑 So a solution is to order more ICs and components that are hard to get. Just by looking at the BOM file and think what will I  🔥BURN 🔥? 😂 What is in low availability and has a long lead time?

Problem kind of solved, right?

Hmm… not if you’re into power electronics. In this specific area you need access to magnetic components. So, you order a sample custom transformer let’s say and wait weeks for it. It arrives, all specs are good, and you realize that you got it wrong and need a revision!

Now what 😵?

👉   Ordering samples, which is part of our platform, involves custom work, people, logistics and a reasonable couple of weeks of lead time is well expected. Can you wait that much?

👉   If no, you can go ahead and use the tool to build your own stuff, right away! All you need are the bobbins, cores, wires, some insulating tapes, to make a proof of design sample.

💥 The PSFB topology💥

Starting right away with a 1kW transformer I built some years back when I had no idea what Frenetic was, and no money to order a custom design from anyone...

👉   So, I did all calculations by “hand” using excel and Mathcad files I wrote. I did 3-4 revision to get to an acceptable result and it took me around 2 months to get it right… Let’s see how I could have avoided all revisions, not with the experience I have now, but with what I had back then!

Design stage 1:

The first tab in our tool is the “Waveform” tab, where the basic currents/voltages of a specific topology get calculated. I’ve put in red rectangles the important things. Whatever is in a bluish table/textbox is input to the system.

• What I basically input was that I want a 3.5mH magnetizing inductance transformer (every app note I’ve seen gives you an equation for this), at 100kHz, with 390V input and 20A output current.
• Also, the turns ratio is 4.28 (again you’ll see how to calculate this in a PSFB app note), my output voltage is 48V nominal (battery charging) and the output power is 1000W.

Then you hit “Update Waveform” and all basic currents/voltages are calculated. I know you’re not amazed yet, you can do all this with your own excel spread sheets, but give me a chance to move to the 2^nd stage of the design ❗❗❗

Design stage 2:

Now that’s where it gets interesting!

👉 We are in the tab “List of Design” where the platform suggests 3(or more) completed designs based on the data you’ve input so far! Fully specced, from the core, to the windings, to power losses, until the hotspot temperature under full load.

⭐️   Is this fast enough for you? What other tool do you know that does this? ⭐️  

What we can do at this point is to select one of the designs and the rest of the tabs will be filled out automatically. Of course, you can customize the suggested design on your own, by changing these parameters, on the core/winding tabs as we’ll see.

⭐️   In my opinion this is a very good starting point for everyone! ⭐️  

A 🔑 point here is our Library Designs, that I marked in a bold red rectangular in the last picture. We are very keen on providing tested ready to buy sample solutions in this section.

❗ The idea is that you can choose a proven sample that has passed real tests (not just a simulated design as shown). That’s another speedup in the design process. 🚀 Getting a “plug & play” sample right away. 🚀 

🎁 SPECIAL GIFT FOR FRENETIC NEWSLETTER READERS 🎁

The next session of our High Frequency Magnetics Training program will start on June 1st. We have still some available seats and we want to give the chance to some of our newsletter reader to participate at special conditions: 25% discount 😱

All the info about the Training Program are here.

When you check-out, use the coupon "NL25" and you´ll get a 25% off. This promotion is valid up to Sunday 22nd of May, so hurry up!

You can get the Frenetic SuperPowers and save some money, don´t miss this opportunity...

 WHAT’S COMING NEXT WEEK?

👉 Next week we are going to continue the design process, choosing my custom transformer I mentioned before as a case study. Real tests are on the way as well! If it isn’t working what’s the point of simulations, right?

👉As always, if you have a question or an idea, let me know at sotiris.zorbas@frenetic.ai

Previous Newsletters: here!

 👋  Until next week 👋 

Sotiris Zorbas, MSc 

Power Εlectronics Εngineer