Control the charging current of supercapacitors

#1

Hello,

I am trying to charge supercapacitors with a boost chopper.
I want to charge the SC with a 10A current until they reach their maximum voltage value.
I ve got 12 SC, 2.7V 3000F in series.
When I simulate, the current from the SC is 0 and the current from the source is 500kA, as if there is a short circuit somewhere

I think the problem comes from the sum in my loop because I don t know how to compare current values.
I can not upload anything but does someone can show me example of a charge with current control?

Thank you very much
Guillaume

#2

buck_boost_Mod32V_v4.psimsch (59.1 KB)

I ve attached the files.
Does someone can have a look ?
Thank you
Guillaume

#3

you are not controlling the current, you need to redo your topology and control the current in the inductor instead of the voltage “Vcharge” There are several tutorial videos, like this one:buck current loop, that show how to close the loop on the current. If you are doing voltage control you will get the massive inrush currents that you are seeing. You might also want to do peak current control, there are tutorial videos on that as well. PCMC video

#4

Hi Albert,

I ve changed my topology.
I put the current sensor with the inductor.
I Don’t understand the reaction, it is like there is no loop because the current stays at 0 until the simulation reaches 3s and the the current through the SC goes to 10kA.
Do you have an idea where this phenomenon comes from?

buck_boost_Mod32V_v4_1.psimsch (198.6 KB)

Thank you for your help!
Guillaume

#5

The current does not look to be very controllable with this topology. I’m not sure what is going on please check with a linear load to ensure you are able to control the current properly.