U. Rieder, M. Schrödl, A. Nemecek:
"The TeleDrive - A Sensorless Multistage Linear Positioning Drive Based On External Rotor Permanent Magnet Synchronous Machines";
Talk: PCIM, Nürnberg; 05-20-2003 - 05-22-2003; in: "Proceedings of the fortieth international intelligent motion conference", Tagungsband Intelligent Motion / ZM-Communications GMBH, Tagungsband Intelligent Motion (2003), ISBN: 3-928643-36-3; 89 - 94.

In the paper a multistage linear telescopic positioning drive is presented. It is based on external rotor permanent magnet synchronous motors, their actual rotor positions are evaluated by mathematical methods, the INFORM-method in the low speed range and an emf-based model at high speed. The mechanical construction, the sensorless methods and the control algorithms are explained in detail.

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