🚘 Today I’ve decided to mix my passion for vehicles with your enthusiasm for the Dual Active Bridge designs, and I’ve brought you an interesting one: a design from a Texas Instruments application note that consists of a Level 3 EV charging station.
Lately, we are starting to create bidirectional EV charging stations to have the possibility, in case of instability in the grid, to use the power from the EVs to solve this kind of issue.
⚙️ Starting from the application note previously mentioned, I’ve used the parameters shown in Figure 1 to create a new design in Frenetic Online.
Figure 1. DAB Specs
⚡ Let’s start with the design process! You can check the full design here.
First, we enter the specification in Frenetic, as you can see in Figure 2.
Figure 2. Waveform
After entering the parameters in the waveform tab and checking that our operation point is the one where we want to test the transformer, we can move on to the Core OptimizerTM.
🔎 In the Core OptimizerTM, we are able to see the tradeoffs that we should do regarding volume, turns and core losses. With the graphs shown in Figure 3 and the information that we can get from the different operation points, we can now select the core that better fits our requirements.
Figure 3. Core OptimizerTM
As you can see, the 3C98 material seems to work better for this operation point. This information is directly shown in the tab, that clearly displays how different materials are affected by our operating point.
🤓 Let me show you an example of how to use the core tab.
Once you have selected the core, you can move to the iteration process in the core and winding tabs. The example displayed is testing the 3C95 vs the 3C98 for the same operation point and the same windings.
Figure 4. Core
In Figure 4 I show you the results that I get with different materials, 3C95 and 3C98. You can see that the losses, in the case of 3C95 are around 30W, while with the material 3C98 the losses are reduced to 27 W, 3W less. We can test different operation points for this material and we can do all the software iterations needed to have a clear idea of what is the optimal core for my design.
🙌 Let’s move on with the windings!
In Frenetic Online you’re able to simulate how the wire and winding arrangement is affecting your complete design: in a couple of minutes, you get the best winding arrangement and wire for your transformer or inductor.
You can change to PS, PSP, PSPS or two chamber, as well as customizing each of the layers in order to have complete control of what you are designing. Then you can change the wires, chose between litz, round or foil and control all the parameters that you can see in Figure 5.
Figure 5. Core
🤯 Usually, it’s quite complicated to find all your files about one project: either you forgot where they were stored or you need to go through a pile of folders until you finally find them. With Frenetic you can have all the information of your project stored in the same place and easy to find.
In the Mechanical tab, you can add all the manufacturing specifications for your design, in order to gather all the information related to your transformer in the same space.
💡 For our case, the DAB of 10kW, I’ve decided to enter the coil former that I will be using for the E56 core and specified the winding arrangement, as well as some manufacturing considerations, as shown in Figure 6.
Figure 6. Mechanical (Manufacturing/ Coil former selected)
💥 Well, we have already completed our design! Fast, wasn’t it?
Figure 7. Datasheet
📥 We can check out all the info on the design in the last tab, the datasheet. Every detail of your design is directly created for you in this document, so you don’t need to create extra files. In Figure 7 you can see all the information displayed in the Frenetic datasheet.
🚀 Have you enjoyed the smoothness of the design process with Frenetic Online? Apply for a demo and explore all the possibilities that our platform offers.
😎 Hope you liked it, and see you next time!
References
Bidirectional, Dual Active Bridge Reference Design for Level 3 Electric Vehicle Charging Stations (no date) Texas Instruments. Available at: ti.com/lit/ug/tidued8/tidued8.pdf?ts=1613343608107&ref_url=https%253A%252F%252Fwww.google.com%252F (Accessed: December 9, 2022).
