I am new to Simulink software and want to design a battery with 8 cells whoose voltages are 12 Volts. Their capacity is 12Ah. Both have internal resistance of 0.1 Ohms. The aim is to obtain a 24 Volts battery pack by arranging these 8 cells. The load will be 10 Ohms. In the simulink i design the following model. However, i cannot see any result on the current measurement part while i can see the 24V in the voltage measurement part. I have some several questions?
1) Even though there is no load connected to the circuitry there is this internal resistance which cause current in the branches.Why there is no indication of current in the scope?
2) I know that there should be a ground and a resistance in the circuit. However, since they are from different librarires they are not connected. I try interfaces but nothing changes.
Anyone who have any idea about these issue please answer this question. If you want to propose another model it is also okey. Thank you for your answers in advance.
Electrical – Battery Design using Matlab Simulink
batteriesbattery-chargingMATLABsimulationsimulink
Related Solutions
internal resistance increases when capacity decreases
these parameters are not directly connected.
Is more correct to say that internal resistance is related to battery discharge current. Indeed, a battery with higher discharge current will have a smaller internal resistance.
For example, a LiPo prismatic cell of 3000mAh used to have a bigger discharge current than a cylindrical LiIon with the same capacity.
Is there any reason you are mixing SimPowerSystems & SimScape?
With the introduction of SimScape "SimPowerSystems", the legacy method of dealing with electrical simulations has become redundant EXCEPT for some legacy blocks and specialised technologies.
The legacy SimPowerSystems does have a more specialised battery model so I can understand why you would want to use that IF it provides features the simscape battery does not (or that you cannot reproduce...)
you can run with both as long as you provide the needed pre-requisites.
I don't see a SimScape reference block nor a solver block. Do they exist.
The actual problem here is an algebraic loop.
the subsystem highlighted within the 1st post. What EXACTLY is in there? I suspect there is some form of SimPowerSystem voltage sensor to bring a signal into the simulink domain, a Simulink-PS converter block to take it into the SimScape domain. This is where it needs to be solved.
Add a memory block in the simulink domain should break the loop and provided the needed initial condition (if you are running continuous consider adding a TF with a small timeconstant todo the same thing)
Best Answer
The battery's internal resistance is IN SERIES with the battery. With no load connected, the battery will not deliver any current, and there will be no voltage dropped across the internal resistance.
With a load connected, the battery will deliver current, which will flow through the internal resistance. This current causes some voltage drop in the internal resistance, reducing the effective voltage of the [battery plus internal resistance].