@inproceedings{vanderGietRotheHerranzGraciaetal., author = {van der Giet, Michael and Rothe, R. and Herranz Gracia, Mercedes and Hameyer, Kay}, title = {Analysis of noise exciting magnetic force waves by means of numerical simulation and a space vector definition}, series = {XVIII International Conference on Electrical Machines, ICEM}, booktitle = {XVIII International Conference on Electrical Machines, ICEM}, language = {en} } @inproceedings{HerranzGraciaHameyer, author = {Herranz Gracia, Mercedes and Hameyer, Kay}, title = {Effect of non-sinusoidal currents on the acoustic noise excitation of induction motors}, series = {13th IGTE Symposium}, booktitle = {13th IGTE Symposium}, language = {en} } @inproceedings{HerranzGraciaHameyer, author = {Herranz Gracia, Mercedes and Hameyer, Kay}, title = {Comparision of numerical methods for the prediction of cogging torque in 2D and 3D}, series = {13th IGTE Symposium}, booktitle = {13th IGTE Symposium}, language = {en} } @inproceedings{JonasLengsfeldJungetal., author = {Jonas, Steffen and Lengsfeld, Sebastian and Jung, Marco and Ponick, Bernd and Herranz Gracia, Mercedes and Spagnolo, Aristide and Schleicher, Klaus, and Sch{\"a}fer, Klaus}, title = {Design of a Medium Voltage Generator and Power Converter for High Power Wind Energy Conversion Systems}, series = {2020 55th International Universities Power Engineering Conference (UPEC)}, booktitle = {2020 55th International Universities Power Engineering Conference (UPEC)}, doi = {10.1109/UPEC49904.2020.9209886}, pages = {1 -- 5}, language = {en} } @article{HerranzGraciaHameyer, author = {Herranz Gracia, Mercedes and Hameyer, Kay}, title = {Influence of the magnetic anisotropy on electrical machines}, series = {Advanced Computer Techniques in Applied Electromagnetics - Studies in Applied Electromagnetics and Mechanics}, volume = {30}, journal = {Advanced Computer Techniques in Applied Electromagnetics - Studies in Applied Electromagnetics and Mechanics}, doi = {10.3233/978-1-58603-895-3-39}, pages = {39 -- 46}, abstract = {Non grain-oriented electrical steel has an inherent anisotropy, which is normally neglected in the calculation of electrical machines. Moreover, the magnetic anisotropy is usually measured in small material samples. Due to the cutting effect, the magnetic anisotropy in the machine is not the same as in the sample. In this paper, the magnetic anisotropy is considered as a global problem. A method to measure it is presented and its influence on the electromagnetic and acoustic behavior is considered through the example of an induction motor.}, language = {en} } @article{HafnerHenrotteHerranzGraciaetal., author = {Hafner, Martin and Henrotte, Francois and Herranz Gracia, Mercedes and Hameyer, Kay}, title = {An Energy-Based Harmonic Constitutive Law for Magnetic Cores With Hysteresis}, series = {IEEE Transactions on Magnetics}, volume = {44}, journal = {IEEE Transactions on Magnetics}, number = {6}, publisher = {IEEE}, doi = {10.1109/TMAG.2007.916141}, pages = {922 -- 925}, abstract = {In this paper, a phenomenological energy-based material model for ferromagnetic materials under harmonic conditions is presented. The model is based on the concept of a complex effective permeability and an accurate representation of energy is adopted as identification criteria. The material model is implemented in a time-harmonic finite element model, which allows to solve for the loss characteristics of electromagnetic devices. Identification is based on measured hysteresis loops and no additional fitting parameters are required. Hysteresis losses in a ferromagnetic C-core and a ferromagnetic torus are simulated and compared to the results obtained by means of tabulated loss characteristics.}, language = {en} } @inproceedings{MuellerHeilmannHerranzGraciaetal., author = {M{\"u}ller, Marcel and Heilmann, Marcel and Herranz Gracia, Mercedes and Kempkes, Joachim and H{\"a}fner, Martin and Becher, Manuel}, title = {Consideration of the influence of manufacturing tolerances in the design process of electrical machines using the example of a permanent magnet synchronous machine}, editor = {Forschungsvereinigung Antriebstechnik e.V.,}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:863-opus-47594}, pages = {8}, abstract = {The production process of electrical machines is subject to manufacturing and material tolerances. These tolerances have an influence on both, the mean torque and the torque ripple. Consequently, they exert an active influence on the speed-torque map (operating points), as well as the equivalent circuit diagram parameters for a permanent magnet synchronous machine, and the operational behavior (efficiency, noise development) of the electrical machine. In addition to striving lower costs, there is a growing emphasis on achieving higher energy efficiency. Thus, an accurate prediction of machine parameters is still essential during the early development process, despite manufacturing-related deviations. In this study, the prediction of machine parameters is demonstrated using the example of a PMSM.}, language = {en} } @inproceedings{SchulerHerranzGraciaKempkesetal., author = {Schuler, Max and Herranz Gracia, Mercedes and Kempkes, Joachim and Heilmann, Marcel}, title = {PyEMMO - a Python based software for the finite element modelling of electrical machines in ONELAB}, series = {15. International conference on electric vehicle drives and e-mobility}, booktitle = {15. International conference on electric vehicle drives and e-mobility}, editor = {Forschungsvereinigung Antriebstechnik e.V.,}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:863-opus-55489}, pages = {179-184}, abstract = {Multi-objective optimizations are almost essential in the design process of electrical machines due to constantly increasing requirements for efficiency and power density. In this context, open-source simulation software offers the possibility to parallelize calculations free of license costs and thus to achieve a reduced calculation time. This paper presents the software project PyEMMO (Python Electrical Machine Modeling in ONELAB) for the finite element simulation of electrical machines in the open source program ONELAB. The object-oriented program structure and the objectives of the project are the main focus. Furthermore, the latest features are discussed, which include the geometry definition via a toolbox system, the simulation data interface based on the JSON file format and the calculation of iron losses.}, language = {de} } @inproceedings{HeilmannSteckelSchuleretal., author = {Heilmann, Marcel Norbert and Steckel, Richard and Schuler, Max and Keller, Daniel and Gracia, Mercedes Herranz and Kempkes, Joachim}, title = {Improved Calculation of the Force Density in the Air Gap of a Squirrel Cage Induction Machine for NVH Simulation}, series = {2024 International Symposium on Power Electronics, Electrical Drives, Automation and Motion (SPEEDAM)}, booktitle = {2024 International Symposium on Power Electronics, Electrical Drives, Automation and Motion (SPEEDAM)}, publisher = {IEEE}, doi = {10.1109/SPEEDAM61530.2024.10609211}, pages = {812 -- 818}, language = {en} }