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EMR examples


It should be noticed that since 2011 the triangle pictogram (mechanical conversion) has been replaced by a square pictogram (mono-physical conversion). More information.

Example of an Electric vehicle

The studied system is an Electric Vehicle (EV) equipped with a gearbox, a differential and two driven wheels (Fig. 2). In this initiation unit, in order to simplify the study, the induction machine can be replaced by a permanent magnet DC machine supplied by a chopper from the battery.

inversion principle

Fig. 2. Scheme of the EV example.

From the relationships of each component, the EMR of the traction system of the EV is deduced according to the EMR pictogram (upper part of Fig. 3). Then, the control scheme is deduced by an inversion step-by-step of the EMR (lower part of Fig. 3). All relationships of modelling and control can be found in [Bouscayrol 2007]

inversion principle

Fig. 3. EMR and deduced control of the studied EV.

Thus example is developed in the Master ASE of the Universitu of Lille, as an initiation level of EMR. The students have a simulation project where they have to develop the simulation of the whole sytem including its control using Matlab-Simulink (Fig. 4).

The use of EMR is an efficient methodology to develop student skills on drive control. A unified and physical modeling is developed, and inversion rules are used to find the control scheme. By using this intermediary step, they can easily connect other scientific fields such as power electronics, electrical machine, mechanics and automatic control.

In this initiation level, only simple systems with DC machines are studied in order to focus attention on the physical integral modeling, the interaction principle and the inversion-based control. Evaluations of the unit show a very good acquisition of fundamentals on drive control. Because of the attractive graphical description, a lot of students choose the expert level unit. In this second unit, the students study more complex drives, such as AC machines drives, multi-motor applications, recent traction systems, renewable energy systems. Advanced control can thus be taught. Finally, the students can thus used these skills in the Master final projectsor PhD for more complex systems.

inversion principle Fig. 4. Matlab-Simulink model of the EV traction system.

Exemple of more complex traction systems

EMR and inversion-based control of a parraell Hybrid Electroc Vehicle are depicted [Lhomme 07] (Fig. 5). Other examples will be given in the workshop: wind energy conversion systems, hybrid storage system for PV, series HEV, series-parallel HEV, automatic subway, fuel cell systems, multi-drive paper processing...

inversion principle Fig. 5. EMR and inversion-based control of a parallel HEV with a clutch.

[Bouscayrol 07] A. Bouscayrol, A. Bruyère, P. Delarue, F. Giraud, B. Lemaire-Semail, Y. Le Menach, W. Lhomme, F. Locment, "Teaching drive control using Energetic Macroscopic Representation - initiation level", EPE'07, Aalborg (Denmark), September 2007.
[Lhomme 07] W. Lhomme, "Energy managment of Hybrid Electric Vehicles based on Energetic Macroscopic Representation", PhD Dissertation, University of Lille, (Text in French), November 2007, (common work of L2EP Lille and LTE-INRETS according to MEGEVH network)

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