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Generate Feed-Forward Flux Parameters

This example shows how to create lookup tables for an interior permanent magnet synchronous motor (PMSM) controller that characterizes the d-axis and q-axis flux as a function of d-axis and q-axis currents.

To generate the flux parameters for the Flux-Based PM Controller block, follow these workflow steps.

Step 1: Load and Preprocess Data

Load and preprocess this nonlinear motor flux data from dynamometer testing or finite element analysis (FEA):

  • d- and q- axis current

  • d- and q- axis flux

  • Electromagnetic motor torque

Import and preprocess the raw PMSM data from a |xlsx| file captured from a dynamometer or another CAE tool.

fileName = "PMSM_150kW.xlsx";

opts = detectImportOptions(fileName);

% read units if they are defined in the second row
if opts.DataRange=="A3"                 
    opts.VariableUnitsRange = "A2";

rawData = readtable(fileName, opts);

Load the data columns.

lambda_d = rawData.Psi_d;
lambda_q = rawData.Psi_q;
id = rawData.I_d;
iq = rawData.I_q;

Step 2: Generate Evenly Spaced Data

The raw current and flux tables are recorded in a single column format. Convert them into evenly spaced data matrices using 2D interpolation.

Set the spacing for the table rows and columns.

flux_d_size = 51;
flux_q_size = 51;

Use interpolation to get higher resolution.

id_new = linspace(min(id),max(id),flux_d_size);
iq_new = linspace(min(iq),max(iq),flux_q_size);
currentBreakpoints = {id_new,iq_new};

Visualize the Flux Surfaces

The d-axis flux, λd, is a function of d-axis current, Id, and q-axis current, Iq.

lambda_d_new = fitlookupn(currentBreakpoints,[id,iq],lambda_d,ShowPlot=true);
title("Flux d [Wb]");
xlabel("Id [A]")
ylabel("Iq [A]");

The q-axis flux, λq, is a function of d-axis current, Id, and q-axis current, Iq.

lambda_q_new = fitlookupn(currentBreakpoints,[id,iq],lambda_q,ShowPlot=true);
title("Flux q [Wb]");
xlabel("Id [A]")
ylabel("Iq [A]");

Step 3: Set Block Parameters

Set these Flux-Based PM Controller block parameters to the values assigned in the script.

Vector of d-axis current breakpoints, id_index


Vector of q-axis current breakpoints, iq_index


Corresponding d-axis flux, lambda_d


Corresponding q-axis flux, lambda_q


See Also


Related Topics