- Magnetic equivalent circuit modeling of permanent magnet synchronous motors (PMSM)
- Systematic incorporation of magnetic saturation and non-sinusoidal field characteristics
- Optimal torque control
- Sensorless methods for the position estimation of PMSM

Permanent magnet synchronous motors (PMSM) are applied in many industrial applications as e.g. robotics due to their high torque capabilities and their high energy efficiency. Field-oriented control is the industrial standard for the control of PMSMs. This control strategy is based on a transformation of the angle-dependent quantities of the PMSM on a dq0-coordinate frame which is fixed with the rotor. The design is typically based on the assumption of magnetic linearity and sinusoidal field characteristics of the PMSM.

Modern motor constructions frequently apply single tooth windings and an inhomogeneous air gap. This results in PMSMs where the assumption on a sinusoidal field characteristics is more or less violated. Moreover, PMSM are frequently operated up to regions with significant magnetic saturation. Thus, the assumption of the classical field-oriented control are frequently more or less violated in many practical applications.

In this research cooperation with Bernecker and Rainer Industrieelektronik GmbH (B&R), methods for systematic mathematical description of PMSMs with pronounced magnetic saturation and non-sinusoidal field characteristics are examined. Here, the magnetic equivalent circuit modeling (MEC) approach, which is based on an approximation of the magnetic system of the PMSM by magnetic resistances (reluctances) and magneto-motive force-sources (coils, permanent magnets), see Fig. 1.

Network theory, which is well known from electric circuits, is utilized to systematically obtain the mathematical model for arbitrary motor construction with rather complex magnetic equivalent networks, see, e.g., Fig. 2. Moreover, it is easily possible to systematically include magnetic saturation and non-sinusoidal field characteristics.

The resulting MEC-models feature a rather low model complexity, which makes them suitable for a model-based design of control strategies. In this research project optimal control strategies for the indirect torque control of PMSMs, while minimizing the losses of the PMSM at the same time, are developed. These control strategies allow to significantly improve the torque control accuracy in comparison to a classical field oriented control strategy (dq), see, e.g., Fig. 3.

The model-based approach allows to easily adopt the control strategies to other construction sizes and types of PMSMs. In particular, the control strategies can also be applied to linear motors. Moreover, the developed mathematical models are a good basis for the sensorless estimation of the position of PMSM.

- D. Faustner, W. Kemmetmüller, and A. Kugi, Flatness-Based Torque Control of Saturated Surface-Mounted Permanent Magnet Synchronous Machines, IEEE Transactions on Control Systems Technology, vol. 24, iss. 4, p. 1201–1213, 2016.

[BibTex] [Download]@Article{Faustner16, Title = {Flatness-Based Torque Control of Saturated Surface-Mounted Permanent Magnet Synchronous Machines}, Author = {Faustner, D. and Kemmetm{\"u}ller, W. and Kugi, A.}, Journal = {IEEE Transactions on Control Systems Technology}, Pages = {1201--1213}, Volume = {24}, Year = {2016}, Number = {4}, Doi = {10.1109/TCST.2015.2501345}, ISSN = {1063-6536}, }

- D. Faustner, W. Kemmetmüller, and A. Kugi, Experimental Parameterization of a Design Model for Flatness-Based Torque Control of a Saturated Surface-Mounted PMSM, in Proceedings of the 7th IFAC Symposium on Mechatronic Systems & 15th Mechatronics Forum International Conference, Loughborough, UK, 2016, p. 575–582.

[BibTex]@InProceedings{Faustner16a, author = {Faustner, D. and Kemmetm\"uller, W. and Kugi, A.}, title = {Experimental Parameterization of a Design Model for Flatness-Based Torque Control of a Saturated Surface-Mounted PMSM}, booktitle = {Proceedings of the 7th IFAC Symposium on Mechatronic Systems \& 15th Mechatronics Forum International Conference}, year = {2016}, volume = {49}, number = {21}, month = {9}, pages = {575--582}, doi = {10.1016/j.ifacol.2016.10.663}, address = {Loughborough, UK}, issn = {2405-8963}, }

- D. Faustner, W. Kemmetmüller, and A. Kugi, Magnetic Equivalent Circuit Modeling of a Saturated Surface-Mounted Permanent Magnet Synchronous Machine, in Proceedings of the 8th Vienna International Conference on Mathematical Modelling (MATHMOD), Vienna, Austria, 2015, p. 360–365.

[BibTex]@InProceedings{Faustner15, author = {Faustner, D. and Kemmetm\"uller, W. and Kugi, A.}, title = {Magnetic Equivalent Circuit Modeling of a Saturated Surface-Mounted Permanent Magnet Synchronous Machine}, booktitle = {Proceedings of the 8th Vienna International Conference on Mathematical Modelling (MATHMOD)}, year = {2015}, month = {2}, pages = {360--365}, doi = {10.1016/j.ifacol.2015.05.033}, address = {Vienna, Austria}, }

- D. Faustner, W. Kemmetmüller, and A. Kugi, Field Weakening in Flatness-Based Torque Control of Saturated Surface-Mounted Permanent Magnet Synchronous Machines, in Proceedings of the 2015 IEEE Conference on Control Applications (CCA), Sydney, Australia, 2015, p. 858–863.

[BibTex]@InProceedings{Faustner15a, author = {Faustner, D. and Kemmetm\"uller, W. and Kugi, A.}, title = {Field Weakening in Flatness-Based Torque Control of Saturated Surface-Mounted Permanent Magnet Synchronous Machines}, booktitle = {Proceedings of the 2015 IEEE Conference on Control Applications (CCA)}, year = {2015}, publisher = {IEEE}, month = {9}, pages = {858--863}, doi = {10.1109/CCA.2015.7320725}, address = {Sydney, Australia}, }

- W. Kemmetmüller, D. Faustner, and A. Kugi, Optimale Nichtlineare Regelung von permantenterregten Synchronmaschinen, at – Automatisierungstechnik, vol. 63, iss. 9, p. 739–750, 2015.

[BibTex] [Download]@Article{Kemmetmueller15a, Title = {Optimale Nichtlineare Regelung von permantenterregten Synchronmaschinen}, Author = {Kemmetm\"uller, W. and Faustner, D. and Kugi, A.}, Journal = {at -- Automatisierungstechnik}, Pages = {739--750}, Volume = {63}, Year = {2015}, Number = {9}, Doi = {10.1515/auto-2015-0041}, }

- W. Kemmetmüller, D. Faustner, and A. Kugi, Optimal torque control of permanent magnet synchronous machines using magnetic equivalent circuits, Mechatronics, vol. 32, p. 22–33, 2015.

[BibTex] [Download]@Article{Kemmetmueller15b, Title = {Optimal torque control of permanent magnet synchronous machines using magnetic equivalent circuits}, Author = {Kemmetm\"uller, W. and Faustner, D. and Kugi, A.}, Journal = {Mechatronics}, Pages = {22--33}, Volume = {32}, Year = {2015}, Doi = {10.1016/j.mechatronics.2015.10.007}, ISSN = {0957-4158}, }

- W. Kemmetmüller, D. Faustner, and A. Kugi, Modeling of a permanent magnet synchronous machine with internal magnets using magnetic equivalent circuits, IEEE Transactions on Magnetics, vol. 50, iss. 6, 2014.

[BibTex] [Download]@Article{Kemmetmueller14, Title = {Modeling of a permanent magnet synchronous machine with internal magnets using magnetic equivalent circuits}, Author = {Kemmetm{\"u}ller, Wolfgang and Faustner, David and Kugi, Andreas}, Journal = {IEEE Transactions on Magnetics}, Volume = {50}, Year = {2014}, Number = {6}, Doi = {10.1109/TMAG.2014.2299238}, }

Univ.-Prof. Dr.techn. Andreas Kugi

David Faustner