Generate Current Controller Calibration Tables for Torque and Speed-Based Motor Controllers

Using the Model-Based Calibration Toolbox™, you can generate optimized calibration tables for torque and speed-based motor controllers.

Based on nonlinear motor flux linkage and torque data, the calibration tables maximize motor efficiency by optimizing:

• Maximum torque per ampere (MTPA)

• Maximum torque per volt (MTPV)

The calibration tables are d- and q- axis reference currents as functions of one of these combinations:

• Motor speed and absolute torque

• Motor speed and torque percent

• Maximum flux and absolute torque

• Maximum flux and torque percent

Torque percent is a percentage of maximum torque at each speed.

You can import data, fit a model, and optimize the data based on objectives and constraints. To generate optimized current calibration tables as functions of motor speed and torque percent, follow these steps.

Steps	Description
Collect and Process Motor Data	Collect the nonlinear motor flux data from dynamometer testing or finite element analysis (FEA). For this example, file PMSM_MBCData.xlsx contains this required data: Total flux, Ψtotal, in Wb Allowed flux, Ψmax, in Wb d-axis current, Id, in A q-axis current, Iq, in A Current magnitude, Is, in A Voltage magnitude, Vs, in V Motor torque, Te, in N·m Motor speed, n, in rpm
Prepare Motor Data for Modeling Fit Models to Generate Calibrations	Use a point-by-point model to fit the PMSM_MBCData.xlsx data: Import data. Filter and group data. Fit the model. The permanent magnet synchronous motor (PMSM) maximum efficiency calibration case study contains the model fit.
Generate Calibration Find Maximum Torque Envelope for Motor Calculate Optimal Current Lookup Tables for Motor	Calibrate and optimize the data using objectives and constraints: Create functions. Create tables from model. Run an optimization. Generate and fill optimized current controller calibration tables that are functions of motor torque percent and motor speed. The PMSM maximum efficiency calibration case study contains the calibration results.
Export Results	Export calibration results for use in motor control applications.

References

[1] Hu, Dakai, Yazan Alsmadi, and Longya Xu. “High-Fidelity Nonlinear IPM Modeling Based on Measured Stator Winding Flux Linkage.” IEEE^® Transactions on Industry Applications 51, no. 4 (July/August 2015).

[2] Chen, Xiao, Jiabin Wang, Bhaskar Sen, Panagiotis Lasari, and Tianfu Sun. “A High-Fidelity and Computationally Efficient Model for Interior Permanent-Magnet Machines Considering the Magnetic Saturation, Spatial Harmonics, and Iron Loss Effect.” IEEE Transactions on Industrial Electronics 62, no. 7 (July 2015).

[3] Ottosson, J., and M. Alakula. “A Compact Field Awakening Controller Implementation.” International Symposium on Power Electronics, Electrical Drives, Automation and Motion, July 2006.