Incompatible array sizes error in hppcTest

Hello team,

I am using the Simscape battery toolbox to estimate ECM Parameters from HPPC test data following the similar example provided.

When I load my hppc data, and run hppcTest, I get the error Arrays have incompatible sizes for this operation.

The data has many pulses. However, when I choose only data for 1 pulse, it works fine.

Here is my code snippet -

```

% Load the CSV file

data = readtable('240419_1C_Disharge_HPPC_25.csv');

% Create simple table with renamed columns

hppcData = table(data.Ch7_Time_Second_, data.Ch7_Voltage_V_, data.Ch7_Current_A_, ...

'VariableNames', {'Time', 'Voltage', 'Current'});

% Display to verify

disp('Table created:');

disp(head(hppcData));

disp('Size of table:');

disp(size(hppcData));

% Create hppcTest object

hppcExp25degC = hppcTest(hppcData, ...

'TimeVariable', 'Time', ...

'VoltageVariable', 'Voltage', ...

'CurrentVariable', 'Current', ...

'Capacity', 50, ...

'InitialSOC', 1.0);

```

Answer 1

[Xiangchun]

Hi @Raghunandan Pratoori,

From what has been shared, I can not tell what might have caused the issue. However, you can use debug capabilities in MATLAB to troubleshoot the issue: Debug MATLAB Code Files - MATLAB & Simulink and pinpoint what is causing the array size mismatch.

Alternatively, I highly recommend that we use Model-Based Calibration Toolbox (MBC) for battery Equivalent Circuit Model (ECM) parameter estimation. Please see an example here: Characterize Battery Block Parameters in CAGE - MATLAB & Simulink. In MBC, you only need to write code to organize the experiment data based on HPPC tests, and the optimization is done via an intuitive app. Most importantly, it is capable of estimating multiple typical RC tables (depending on both temperature and SOC) in a few minutes. It can also work with a variety of current profiles beyond HPPC, including drive cycle profiles.

Best wishes,

Xiangchun