@article{KralKapellerGraggeretal., author = {Kral, Christian and Kapeller, Hansj{\"o}rg and Gragger, Johannes V. and Haumer, Anton and Kubicek, Bernhard}, title = {Phenomenon Rotor Fault-Multiple Electrical Rotor Asymmetries in Induction Machines}, series = {IEEE Transactions on Power Electronics}, volume = {25}, journal = {IEEE Transactions on Power Electronics}, number = {5}, publisher = {IEEE}, issn = {0885-8993}, doi = {10.1109/TPEL.2009.2037502}, pages = {1124 -- 1134}, abstract = {In the literature, the effects caused by a single or several adjacently broken rotor bars, or a broken end ring are thoroughly investigated. The phenomenon of various nonadjacently broken rotor bars has not been studied so far in detail. Since nonadjacently broken rotor bars may give rise to fault signatures, which are not directly related with the fault extent, it is important to understand the nature of multiple electrical rotor asymmetries in induction machines. The purpose of this paper is thus to investigate several combinations of electrical rotor asymmetries, to systematically elaborate the phenomena related to the broken bars and end rings. In this paper, a sophisticated simulation model and measurement results are used to analyze the phenomenon rotor fault.}, language = {en} } @incollection{GrabnerGraggerKapelleretal., author = {Grabner, Christian and Gragger, Johannes V. and Kapeller, Hansj{\"o}rg and Haumer, Anton and Kral, Christian}, title = {Sensorless PM-Drive Aspects}, series = {Electronic Engineering and Computing Technology}, booktitle = {Electronic Engineering and Computing Technology}, editor = {Ao, Sio-Iong and Gelman, Len}, publisher = {Springer}, address = {Dordrecht}, isbn = {978-90-481-8775-1}, doi = {10.1007/978-90-481-8776-8_3}, pages = {25 -- 35}, abstract = {The development procedure of permanent magnet drives for sensor less operation beginning from standstill under overload conditions has to consider different design aspects coevally. First, the robust rotor position sensing by test signal enforces a design with a strongly different behavior of the spatial dq-oriented differential inductance values. Therefore, the interior rotor magnet array arrangement is from principle predestinated for the controlled sensor less mode including standstill. Fortunately, in order to reduce costs, the distinct reluctance torque capability of such interior magnet arrangement is additionally used for a significantly increased torque by applying a pre-oriented stator current space vectors within the quasi-steady control.}, language = {en} }