UCC28951-Q1: EV charger station Design

Part Number:UCC28951-Q1

Hello,

My team is in charge of designing an EV charger station and we are looking at products available to create such system. I have a few questions in regards of design complexity, performance and available data to design this charger. I stumbled upon “DC/DC Converters for Automotive Applications” series and I’ve found that the UCC28951-Q1 would be perfect for our application.

I have a series of questions in regards of the picture below:

1. The only external hardware to perform CC-CV is two TLV316-Q1, one LM4132-Q1, and a current sensor, is this right? No need for a compensator network/control loop? Any caveats?

2. Why are the diodes opposing the TLV output? Isn’t that supposed to be ‘ORing’ those outputs?

3. In the case of needing to change the CC-CV reference, do I change the LM4132 output to; for example, accommodate other types of battery voltages and charging currents?

This is for the case of just one charger/power stage. In the case I want to create a charging station with multiple stages giving me a multiplicative factor of n for n staged chargers, how can I achieve this with the UCC28951-Q1? Do I need a special control scheme to achieve this or the UCC28951-Q1 will regulate them in order to achieve CC-CV?

In terms of the design:

• How does the design tool accommodate with this charger design?

• Can I use the same tool for the charger?

• How about the SPICE example?

• What type of transformer model did you use to design the magnetics in this case? What types of assumptions do I have to make?

• Same with the current sensor transformer

• How do I turn off the SR scheme to accommodate a full bridge rectifier at the output?

• What would be better for the charger, two output “center tapped” or a single output transformer?

• How would the design change if I want to boost the voltage? I know the PSFB is a buck derived converter but, how do I convert it into a boost? Is it just playing with the transformer turns ratio or is it something else?

• Is there a mathematical model or an open loop model of this scheme?

• Any other tips and tricks using this device? Books etc.?

Thanks for the help and very respectfully,

Carlos Ramos, Electrical Engineer

Resonant Aero