Pulse Charging Simulation for a Li-ion Battery Pack in PLECS

PLECS
,
1

I am currently working on a simulation study in PLECS related to Li-ion battery charging techniques. My aim is to implement and compare different charging profiles, and I am now trying to model the Pulse Charging technique.

In my model, I would like to apply a pulsed charging current to the battery pack instead of a continuous constant current. The basic idea is to charge the battery with current pulses and include short rest periods between the pulses. However, I am not fully sure about the best way to generate the pulse current reference and connect it properly to the current control loop in PLECS.

I would appreciate guidance on the following points:

  1. How can I generate a suitable pulse current reference in PLECS?

  2. Should the pulse profile be created using a signal generator, lookup table, or a custom control block?

  3. How should the pulse current reference be connected to the battery charger control structure?

  4. Are there any important points to consider regarding pulse frequency, duty ratio, rest time, or simulation step size?

  5. If anyone has a simple example model or reference structure for pulse charging, it would be very helpful.

The battery charger model is intended for a Li-ion battery pack, and the charging current should periodically switch between a defined charging current level and zero during the rest intervals.

Thank you in advance for your help and suggestions.

Best regards,

2

Hi bugraokumus,

The answers to questions 1 through 4 are highly dependent on what you are trying to implement.

If your intention is to implement the actual power electronics converter and charging algorithm, then you will need to fully design the converter, control loops, and charging strategy.

On the other hand, if your goal is simply to create a behavioral model of the charger, then the implementation can be much simpler. For example, you could use:

  • a Pulse Generator block for fixed-frequency charging pulses, or
  • a Variable Frequency PWM component to inject charging current into the battery terminal at the desired rate and duration.

While a complete end-of-charge pulse charging algorithm has not been implemented in an example model, you could extend the On-board Charger demo model included with the TI C2000 Target Support Package, or use the following application example as a starting point:

I would expect that you would need to add an outer supervisory loop that requests charging pulses with the desired duration and repetition frequency for the end-of-charge behavior.

As for the exact pulse pattern and charging profile, that is typically developed by battery design engineers and depends heavily on the battery chemistry and application requirements. You would likely need to do some research into pulse-charging algorithms appropriate for your specific application.

Hope this helps!

1 Like