Constant Three-phase load with harmonic content

I am trying to determine how to use the Simulink Harmonic Filter example to show that the filters can remove harmonics. I was able to export the harmonic data (1st through 63rd) from the power monitoring equipment in my plant into an excel spreadsheet. I need like to replace the Rectifier in the example with my actual three-phase current data.

This example can be opened using the following command: openExample('simscapeelectricalsps/HarmonicFiltersExample')

I am using Simscape\Electrical\SpecializedPowerSystems components. I saw a Constant Current Load (Three-Phase) block; however, the frequency cannot be changed and this block is for Simscape Electrical. Something like this block from Specialized Power System components would be perfect if the frequency was selectable. I would like to stick with the Specialized Power System components.

Here is the Harmonic data taken from our plant power meter.

Answer 1

[Ruchika Parag]

Hi David, to replace the Rectifier in the Simulink Harmonic Filter example with your actual three-phase current data, you can follow these steps:

1. Prepare Your Data: Ensure your Excel spreadsheet with the harmonic data is well-formatted. You will need to import this data into MATLAB.

2. Import Data into MATLAB:

data = readtable('harmonic_data.xlsx');
% Assuming your data has columns 'Time', 'PhaseA', 'PhaseB', 'PhaseC'
time = data.Time;
phaseA = data.PhaseA;
phaseB = data.PhaseB;
phaseC = data.PhaseC;

3. Create a Timeseries Object:

ts_phaseA = timeseries(phaseA, time);
ts_phaseB = timeseries(phaseB, time);
ts_phaseC = timeseries(phaseC, time);

4. Modify the Simulink Model:

• Open the Simulink model from the example.
• Remove the Rectifier block.

5. Configure the Three-Phase Programmable Voltage Source:

• Double-click the block to open its parameters.
• Set the Phase-to-phase RMS voltage and Frequency according to your system requirements (e.g., 50 Hz or 60 Hz).
• For the Time variation of the voltage sources, set the Time variation to External to use the timeseries data.

6. Use From Workspace Blocks:

• Add three From Workspace blocks from the Simulink library.
• Configure each block to use the timeseries objects created (ts_phaseA, ts_phaseB, ts_phaseC).

7. Connect the From Workspace Blocks:

• Connect the outputs of the From Workspace blocks to the Three-Phase Programmable Voltage Source block.
• Ensure the connections are correct for phases A, B, and C. Save and run the simulation.

By following these steps, you should be able to replace the Rectifier block with your actual three-phase current data and observe the effect of the harmonic filters in the Simulink Harmonic Filter example. Hope this helps!

Answer 2

[David Cole]

Ruchika,

Thank you for the response.

I am having a little difficulty following your example. The first column of data is the harmonic number of the current data. Columns 2-4 represent the RMS current values (phases A, B, and C) of the associate harmonic number. Also, when I opened the parameters for my Three-Phase Programmable Voltage Source (SpecializedPowerSystems\Source\SignalGeneratorSources) it did not have an External selection in the Time varation of parameter. I would utilizes blocks from the Specialized Power Systems section.

Regards,

David