Marcel Jufer

Modeling and test contactless inductive energy transmission

More and more applications require contactless energy transmission: machine tools (rotating table, x–y tables), robotics, electric vehicle loading systems, high speed transportation, a.s.o. The electromagnetic inductive technique is a good solution in a wide range of power. The aim of this paper is to assess solutions for electric vehicles and rotating systems. This way, ironcore rotative transformer and ironless linear transformer are considered. The specific methodology and equations to design such transformers will be presented. A parametric analysis will show the main limits and finally, some design results will also be presented for a high speed underground transportation system – the Swissmetro project.

Linear reluctant transducer for vibrator application

This paper presents a solution to design a linear reluctant transducer characterized by a quasi-linear force versus the displacement and to simplify the electronic supply as well as the control. The model, the verification by a finite element simulation and an application as a vibrator generation system are developed. >

Electric drive system for automatic guided vehicles using contact-free energy transmission

Four technologies, combining mainly innovative solutions, offer the possibility of clean and flexible vehicles, all using only electricity. The main common components are contact-free energy transmission, storage on super-capacitors, holonome axles integrating wheel-motors and automatic guiding. Moreover, the complete energetic chain is managed by power electronics. Their applications are mainly in the field of public and industrial transportation. Several applications are described: electric busses, automatic guided vehicles for container handling, automatic people movers and automatic surveillance vehicles. For more information please visit http://www.numexia.com/.

Traction in Europe

The development of electric drives in traction is strongly influenced by the historical choices in matter of supply network : frequency, voltage, connection to the main network, etc. However, the choice is made more and more on electric drives by asynchronous motors, supplied by frequency changers. It is thus the whole of the conditioning electronic system of the network which is specific to each case.

Perspectives on Electrical Motors

Since the beginning of electromechanics, the main motors produced and applied have been asynchronous, dc and universal motors. About 30 years ago, an important evolution occurred, triggered by the stepping motor revolution. New families of motors and electric drives appear: synchronous self-commutated motors; switched reluctance motors; special transducers and actuators. Four main evolution factors may be identified and are analyzed: the application requirement; the motor technology and materials; the peripheral technologies, mainly based on electronics and microprocessors; the design possibilities, based on parametric analysis. An important trend in the field of electric drives, including motor, power electronics, commutation, control and communication is the smart motor or integrated electric drive. This development is mainly based on function and component integration. A specific section is devoted to large motor evolution, mainly related to power electronics for current and speed control.