Simulink control a battery through breaker

I an using Simulink/SimPowerSystems and want to discharge a battery and control it open or close through breaker1 to breaker3. I try to avoid the leakage current, so I build a big resistor around the battery. My model looks like this:

and the code:

function [CR1,CB1,CB2,CB3] = fcn(SOC1)
CR1 = 1;
CB2 = 0;
CB3 = 0;
if (SOC1>=80)
    CB1 = 1;
    CB2 = 0;
    CB3 = 1;
elseif (SOC1<40)
    CB1 = 1;
    CB2 = 1;
    CB3 = 0;
end

The scope which shows the voltage , SOC and current of battery looks like this:

As you can see, when SOC =40, I open the breaker(not connected) and I found that the SOC of battery drop rapidly even the battery doesn't connect with other component. I don't know what's going on here...

[Ahmad Hijazi]

You can try using an ideal switch instead of a breaker and loose the resistor

Answer 1

[Aryan Ritwajeet Jha]

As per the documentation of Breaker, it is not advised to use it in DC applications (such as battery charging/discharging). In this case use a combination of Ideal Switch and Staircase Generator (an example they have given in the doc of Breaker, power_breaker shows you how to use the same). I had the same problem which is solved by doing the above manoeuvre.

[Sankarshan Durgaprasad]

Thank you it works!

Answer 2

[SONG Lyu]

I have the same problem with your model, I also don't know why there is a sawtooth signal at the bottom, in my opinion, I think the switches are continuing change when the SOC is dropping to the trigger value.

Answer 3

[SONG Lyu]

Fixed, try using the different solver. previously, I use the ode 45, then I change the solver to ode 1, which can solve the above problem.