Seeking guidance on series/parallel grouping implementation in Simscape for efficient modeling of complex systems

The battery module has "NumSeriesAssemblies" set to 13, meaning it consists of 13 series-connected assemblies. Each assembly could represent a group of cells connected in series.

Now, let's examine the SeriesGrouping and ParallelGrouping parameters:

1. SeriesGrouping: [1 11 1] The SeriesGrouping parameter indicates the number of cells in each series-connected assembly. In this case, it is set to [1 11 1], which means the battery module has a series connection of 1 cell, followed by 11 cells, and finally, another series connection of 1 cell.
2. ParallelGrouping: [1 1 1] The ParallelGrouping parameter indicates the number of series-connected assemblies in parallel. Here, it is set to [1 1 1], which implies that there is only one assembly in parallel.

Based on the SeriesGrouping, with 13 series-connected assemblies and each assembly containing 11 cells, we would expect the total cell voltage to be 44V (11 cells * 4V per cell). However, you mentioned that after running the simulation, the cell voltage shows as 4V instead of 44V.

batterymodule =

Module with properties:

NumSeriesAssemblies: 13

ParallelAssembly: [1×1 simscape.battery.builder.ParallelAssembly]

ModelResolution: "Grouped"

SeriesGrouping: [1 11 1]

ParallelGrouping: [1 1 1]

please help me to solve this.

[Ayush]

Hey Rushikesh,

I understand that while using battery module, you are noticing a discrepancy between the expected cell voltage and the actual cell voltage that is being observed in the simulation.

To assist you further, I kindly request the model and replication steps you followed to reproduce the issue on your end. This will enable me to analyze the issue accurately and provide you with an appropriate solution.

In the meantime, to solve this issue, you can try out the following workarounds:

1. Simulation setup: Double-check the simulation setup to ensure that all parameters and initial conditions are correctly set. Verify that there are no errors or inconsistencies in the simulation configuration.
2. Cell model: Review the model used for the individual cells in the battery module. Ensure that the cell model accurately represents the behavior of the cells and that there are no limitations or assumptions affecting the voltage calculation.
3. Module configuration: Verify that the battery module's parameters, including “NumSeriesAssemblies”, “SeriesGrouping”, and “ParallelGrouping”, are correctly set. Ensure that there are no typos or errors in these values that could lead to unexpected results.
4. Model resolution: Check the “ModelResolution” property of the Module object. If it is set to "Grouped," ensure that the “SeriesGrouping” and “ParallelGrouping” properties are configured correctly to represent the desired grouping of cells and assemblies.

For more information on Battery Module , you can refer its documentation using this link : Create module of battery parallel assemblies - MATLAB - MathWorks India

Hope this helps!

Regards,

Ayush Goyal

Answer 1

[Xiangchun]

Hi Rushikesh,

vCell in the generated battery pack block is meant for cell level voltage. Therefore, it is 4V instead of 44V. Please see the documentation here Generated Simscape model of battery pack - Simulink (mathworks.com) under the section of "Output" --> "vCell."

Since series grouping is set to [1 11 1], and parallel grouping is set to [1 1 1]. We would expect all those 11 cells to be treated as a lump in the model, and they would have the same cell level voltage. So you could multiple the vCell by 11 to get the voltage for the 11 parallel assemblies (each made of one cell) connected in series.

Best wishes,

Xiangchun