@article{PereiradosSantosLima2022,

title = {Performance Analysis Based on Thermal Aging Tests of Sol-Gel and Polymer Insulated Wires by Enameling and Extrusion Technology},

author = {Giovana Pereira dos Santos Lima and Sonia Ait-Amar and Gabriel Velu and Philippe Frezel and Abdelhamid Boudiba and Mireille Poelman and Arnaud Nicolay and Pierre-Yves Herze},

url = {https://www.mdpi.com/1996-1073/15/14/5164},

doi = {10.3390/en15145164},

issn = {1996-1073},

year  = {2022},

date = {2022-07-01},

journal = {Energies},

volume = {15},

number = {14},

pages = {5164},

abstract = {This research activity aims to evaluate electrical insulation system (EIS) intended for electrical machine winding wires. The evaluation is based on mechanical, thermal, and electrical properties tests following international standards for enameled wires. Dielectric parameters such as dissipation factor, partial discharge inception voltage (PDIV), parallel capacitance, and parallel resistance behavior of different insulator configurations on twisted-pair samples are observed during thermal aging tests. Those configurations are formed of different combinations of dielectric layers based on conventional polymers (polyester-imide (PEI), polyamide-imide (PAI), polyimide (PI)) used as coating wires. A study using two mineral varnishes (silica-based) obtained by the sol-gel process integrated on these classical enamels an outer layer of extrusion of thermoplastic polymer with and without mineral fillers. Given the high consummation of energy and the use of unsustainable materials involving the production of wires, the principal interest of this work is to exploit new configurations of coating wire produced, with less environmental impact than conventional ones. This work investigates the impact of filled resins on the performance of insulating samples and the influence of the use of sol-gel solutions (mineral varnishes) on the insulated wire to increase the thermal class.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Ait-Amar2022a,

title = {Thermal Aging Study of an Anodized Aluminum Strip Wire for Winding and High Temperature Use},

author = {Sonia Ait-Amar and Rania Saoudi and Gabriel Vélu},

url = {https://www.mdpi.com/1996-1073/15/15/5362},

doi = {10.3390/en15155362},

issn = {1996-1073},

year  = {2022},

date = {2022-07-01},

journal = {Energies},

volume = {15},

number = {15},

pages = {5362},

abstract = {Electrical machines are commonly used in industries and transport and are manufactured with enameled wire coils with polymer insulation. In extreme conditions, as in aeronautics and aerospace, where temperatures exceed 280 °C, the organic insulation deteriorates and it is necessary to find another way to insulate winding wires, in order to ensure a longer life duration of the insulation system and a better operating reliability of electric motors in these environments. Ceramics are more resistant to high temperatures than polymers and the proposed study focuses on the temperature dependence of the dielectric properties of anodized aluminum strips for use in high-temperature electrical machine windings. Different dielectric parameters are measured during thermal constraint. The purpose is to determine the temperature index of the anodized strip and propose a thermal stress life model.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Ait-Amar2022,

title = {Interpretation of Eccentricity of an Enameled Wire by Capacitance Measurements},

author = {Sonia Ait-Amar and Abdoulay Koita and Gabriel Vélu},

url = {https://www.mdpi.com/1996-1073/15/8/2802},

doi = {10.3390/en15082802},

issn = {1996-1073},

year  = {2022},

date = {2022-04-01},

journal = {Energies},

volume = {15},

number = {8},

pages = {2802},

abstract = {There are systems dedicated to measuring the eccentricity of enameled wires based on optical and electromagnetic phenomena. However, these methods are limited by the nature of the insulation and the conductor. The proposed solution consists of checking the wire eccentricity by an electrical measurement. Since it is a conductor on which an insulator is placed, the idea consists of forming a capacitor and measuring its capacitance in order to deduce the insulation thickness.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Lecointe2020a,

title = {High temperature machine: Characterization of materials for the electrical insulation},

author = {Jean-Philippe Lecointe and Stéphane Duchesne and Dorin Cozonac and Gabriel Velu and Krzysztof Komceza},

url = {https://www.degruyter.com/document/doi/10.1515/phys-2020-0109/html},

doi = {10.1515/phys-2020-0109},

issn = {23915471},

year  = {2020},

date = {2020-10-01},

journal = {Open Physics},

volume = {18},

number = {1},

pages = {674--682},

abstract = {This paper aims to present and analyze the materials adapted to design a machine that can work with a high current density without any specific cooling system. In other words, the machine is equipped with material that supports high internal temperature, about 500°C. Candidate materials are selected and the authors indicate that inorganic insulation should be preferred for conductors and slot insulations. Tests are carried out on material selection through measurement of the turn-to-turn voltage, insulation resistances, and the parallel capacitances.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Laidoudi2020,

title = {High-power density induction machines with increased windings temperature},

author = {Aicha Laidoudi and Stéphane Duchesne and Fabrice Morganti and Gabriel Velu},

url = {https://www.degruyter.com/document/doi/10.1515/phys-2020-0131/html},

doi = {10.1515/phys-2020-0131},

issn = {23915471},

year  = {2020},

date = {2020-10-01},

journal = {Open Physics},

volume = {18},

number = {1},

pages = {642--651},

abstract = {The increase of the operating temperature of electrical machines is a major challenge in the context of the large-scale use of electricity in many industrial or individual applications such as mobility. Indeed, working at higher temperatures makes it possible to place electrical actuators in critical areas-such as aircraft engines, for example- A nd/or to significantly improve the power-to-weight ratio of the machine. For several applications (deep pumping, ventilation, etc.), the use of the induction machine is still preferred due to cost, simplicity and robustness essentially. The objective of this study is to estimate the possibilities of making a high-temperature squirrel cage induction machine. A significant increase in the operating temperature of a machine would indirectly allow us to envisage an increase in the current density in the active conductors and thus a significant improvement in the power-to-weight ratio. However, this is at the sacrifice of efficiency. The aim of this study is to evaluate this decrease in efficiency correlated with the increase in the temperature to find the best compromise according to the relevant applications. An analytic sizing model has been proposed for the prediction of losses, which will be coupled with a thermal model to predict the temperature in different parts of the machine. This study presents essential information on the influence of temperature on the parameters important for the performance of an induction machine.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Roger2020,

title = {High temperature machines: A comparison between ceramic-coated wires and anodized aluminum strips},

author = {Daniel Roger and Gabriel Velu and Sonia Ait-Amar Djennad and Sylvain Babicz},

editor = {Jean-Philippe Lecointe and Ewa Napieralska and Andrzej Demenko},

url = {https://www.medra.org/servlet/aliasResolver?alias=iospress&doi=10.3233/JAE-209209},

doi = {10.3233/JAE-209209},

issn = {13835416},

year  = {2020},

date = {2020-08-01},

journal = {International Journal of Applied Electromagnetics and Mechanics},

volume = {63},

number = {4},

pages = {715--724},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Zouzou2020,

title = {Modeling and Experimental Characterization of Nickel-Coated Copper Wires for the Design of Extremely High-Temperature Electrical Machines},

author = {Nada Zouzou and Thu Thuy Dang and Stéphane Duchesne and Gabriel Velu and Olivier Ninet},

url = {https://ieeexplore.ieee.org/document/8957369/},

doi = {10.1109/TMAG.2019.2961063},

issn = {19410069},

year  = {2020},

date = {2020-03-01},

journal = {IEEE Transactions on Magnetics},

volume = {56},

number = {3},

pages = {1--9},

abstract = {The requirement for electrical machines operating at extremely high temperatures has prompted researchers to focus on new materials. The use of nickel-coated copper (Cu/Ni) wires can be a promising alternative to copper wires because of their resistance to oxidation at high temperatures. In this article, the characterization of Cu/Ni wires' electrical resistance in the frequency domain as well as the measurement of pure nickel's B(H) curve have been specified. The effect of nickel coated on a copper wire is remarkable in terms of electrical resistance at high frequencies because of the skin effect and eddy currents. An original model has been proposed for the prediction of the electrical resistance. The originality is to consider the bimetallic conductor as a transformer in order to generate its model. Since the analytical calculation is not possible because of the nonlinearity of the nickel's magnetic properties, a new numerical computational method for the determination of the impedances was proposed. The modeling results are correlated with the experimental tests made on 3 Cu/Ni wires: 0.3 mm diameter with 27% of nickel in volume and 0.5 mm diameter with 8 and 18 mu textm nickel thickness. This article, thus, provides essential information about the important parameters for the performance of electrical machines.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Babicz2019,

title = {Improving insulation quality of ceramic insulated conductors by dip coating with boron oxide},

author = {Sylvain Babicz and Gabriel Velu},

url = {https://ieeexplore.ieee.org/document/8624198/},

doi = {10.1109/TDEI.2018.007418},

issn = {1070-9878},

year  = {2019},

date = {2019-02-01},

journal = {IEEE Transactions on Dielectrics and Electrical Insulation},

volume = {26},

number = {1},

pages = {51--55},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{AbabsaMohamed2018,

title = {High-Temperature Magnetic Characterization Using an Adapted Epstein Frame},

author = {Mohamed-Lamine Ababsa and Olivier Ninet and Gabriel Velu and Jean-Philippe Lecointe},

url = {https://ieeexplore.ieee.org/document/8320967/},

doi = {10.1109/TMAG.2018.2811727},

issn = {0018-9464},

year  = {2018},

date = {2018-06-01},

journal = {IEEE Transactions on Magnetics},

volume = {54},

number = {6},

pages = {1--6},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Babicz2017,

title = {Behavior of anodized aluminum strip under sine and square wave voltage},

author = {Sylvain Babicz and Sonia Ait-Amar Djennad and Gabriel Velu and Andréa Cavallini and Paolo Mancinelli},

url = {http://ieeexplore.ieee.org/document/7873458/},

doi = {10.1109/TDEI.2016.005834},

issn = {1070-9878},

year  = {2017},

date = {2017-02-01},

journal = {IEEE Transactions on Dielectrics and Electrical Insulation},

volume = {24},

number = {1},

pages = {39--46},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Babicz2016c,

title = {Dielectric characteristics of an anodized aluminum strip},

author = {Sylvain Babicz and Sonia Ait-Amar Djennad and Gabriel Velu},

url = {http://ieeexplore.ieee.org/document/7736860/},

doi = {10.1109/TDEI.2016.7736860},

issn = {1070-9878},

year  = {2016},

date = {2016-10-01},

journal = {IEEE Transactions on Dielectrics and Electrical Insulation},

volume = {23},

number = {5},

pages = {2970--2977},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Khalfallaoui2015,

title = {Downscaling at submicrometer scale of the gap width of interdigitated Ba0.5Sr0.5TiO3 capacitors},

author = {Abderrazek Khalfallaoui and Ludovic Burgnies and Karine Blary and Gabriel Velu and Didier Lippens and Jean-Claude Carru},

url = {http://ieeexplore.ieee.org/document/7024974/},

doi = {10.1109/TUFFC.2014.006639},

issn = {0885-3010},

year  = {2015},

date = {2015-02-01},

journal = {IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control},

volume = {62},

number = {2},

pages = {247--254},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Velu2014a,

title = {Windings friendly environmental},

author = {Gabriel Velu and Stéphane Duchesne and Daniel Roger},

url = {http://ejee.revuesonline.com/article.jsp?articleId=35618},

doi = {10.3166/ejee.17.277-290},

issn = {21033641},

year  = {2014},

date = {2014-12-01},

journal = {European Journal of Electrical Engineering},

volume = {17},

number = {5-6},

pages = {277--290},

keywords = {},

pubstate = {published},

tppubtype = {article}

}