A. Kampker, H. Heimes, Benjamin Dorn, F. Brans, S. Hartmann, Martin Schaffrath
{"title":"Effects of the reduction of the copper wire cross-section on the welding process in the manufacturing of hairpin stators for electric traction motors","authors":"A. Kampker, H. Heimes, Benjamin Dorn, F. Brans, S. Hartmann, Martin Schaffrath","doi":"10.1109/EDPC56367.2022.10019755","DOIUrl":"https://doi.org/10.1109/EDPC56367.2022.10019755","url":null,"abstract":"The radical transformation of the automotive industry away from the combustion engine and towards the electric drive requires a constant development and improvement of the related components and production processes. One of these processes is the partial removal of the insulation from copper wires in the production of hairpin stators. Currently, the deinsulation is done by mechanical or laser-based methods. The laser-based process is considered to be a comparatively cost-intensive method, whereby stripping rates can be achieved with almost no copper removal independent of variations within the insulation layer thickness of the original copper wire. Mechanical processes, on the other hand, are sometimes seen critically, since a mechanical process always involves a certain amount of removal of the copper raw material to ensure that the insulation layer is completely removed even if the layer thickness varies due to material and manufacturing based tolerances. A critical limit at which copper removal has a negative influence on product functionality has not yet been identified. Therefore, this work focuses on the effects to which the critical process of contacting the hairpins is influenced by the reduction of the copper cross section. For this purpose, hairpins of the same batch are mechanically stripped to different depths, resulting in different reductions of the copper cross-section. The samples are then welded with a constant set of parameters. The varying stripping depths result in both a variation of the copper cross-section and a variation of the gap width between the pins during welding. All other process parameters are identical for all the samples. The welding samples are then metallurgically analyzed and the mechanical, thermal and electrical properties are measured. These results are then analyzed regarding possible interdependencies and evaluated in the context of possible influences on the functionality of the electric drive.","PeriodicalId":297228,"journal":{"name":"2022 12th International Electric Drives Production Conference (EDPC)","volume":"69 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114896228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Seefried, E. B. Schwarz, Fabian Bleier, J. Franke, J. Bergmann, A. Kühl
{"title":"Optimization of the Ultrasonic Crimping Process of High-Frequency Litz Wires by Using Process Data Monitoring","authors":"J. Seefried, E. B. Schwarz, Fabian Bleier, J. Franke, J. Bergmann, A. Kühl","doi":"10.1109/EDPC56367.2022.10019751","DOIUrl":"https://doi.org/10.1109/EDPC56367.2022.10019751","url":null,"abstract":"From a technological point of view, the contacting process of insulated wires to contact elements is one of the most complex steps in electromechanical engineering. To establish an electrical and mechanical connection of winding ends and contact elements, commonly the wire is stripped before the actual contacting process. However, for high-frequency litz wires, consisting of up to several thousand insulated single wires, the stripping process cannot be carried out in advance. Therefore, processes such as hot crimping or ultrasonic crimping, in which the insulation is thermally removed during the crimping process, are used. The latter is characterized by a significantly lower process energy consumption compared to the hot crimping process. It is therefore most attractive for future applications, but process optimization strategies have hardly been addressed in the literature. Within the scope of this publication, several possibilities of optimizing the process of ultrasonic crimping are investigated by means of systematic process data analysis. For this analysis, directly available data from the control system like the required process energy as well as additionally acquired sensor data, such as the sonotrode oscillation, are taken into account and a variation of process control variables as well as the cable lug clamping is conducted.","PeriodicalId":297228,"journal":{"name":"2022 12th International Electric Drives Production Conference (EDPC)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131970690","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Johannes von Lindenfels, Thorsten Ihne, J. Franke, A. Kühl
{"title":"Electric Propulsion Units in aviation - approach for a mechanical permanent magnet rotor design and the related manufacturing concept","authors":"Johannes von Lindenfels, Thorsten Ihne, J. Franke, A. Kühl","doi":"10.1109/EDPC56367.2022.10019761","DOIUrl":"https://doi.org/10.1109/EDPC56367.2022.10019761","url":null,"abstract":"Electric propulsion units are key components for hybridization and electrification of aviation enabling decarbonization and emission reduction. This application is characterized by significant requirements regarding reliability and power density. This paper deals with a specific mechanical rotor design for Electric Propulsion Units configured as Halbach array and its related manufacturing process. First, existing rotor configurations of electric propulsion units are discussed. Based on this analysis optimization potentials regarding air gap minimization, cooling and retaining of centrifugal forces are introduced. The derived reference design compromises a modular setup of the magnetic active part including combinations of form fit and adhesive bond for all relevant interfaces. The individual advantages and disadvantages of the design as well as further optimization potentials are evaluated based on simulative and experimental investigations. The selected design correlates with a specific assembling and magnetization process which is also discussed. Due to a high number of single parts the assembling is performed as multistage process. The magnetization is conducted applying a sub-assembly strategy to avoid manufacturing problems. Finally, an outlook is given with focus set on the aviation compliant certification process.","PeriodicalId":297228,"journal":{"name":"2022 12th International Electric Drives Production Conference (EDPC)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128092648","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Effect of Higher-Strength Low-Loss Electrical Steel on the Electric Energy Saving of Traction Motors Considering Thermal Analysis","authors":"Ahmed Abouelyazied, L. Vandenbossche, Lisa Lastra","doi":"10.1109/EDPC56367.2022.10019748","DOIUrl":"https://doi.org/10.1109/EDPC56367.2022.10019748","url":null,"abstract":"Higher-strength low-loss electrical steel (ES) grades have shown a noticeable energy saving of interior permanent magnet (IPM) traction motors. This energy saving is achieved by the optimal rotor design enabled by the high mechanical yield strength feature of the utilized ES grade as well as its low loss property. In previous works, the energy saving was explored ignoring the thermal analysis. In practice, thanks to the lower dissipated heat loss, the winding resistance as well as permanent magnet are less prone to degradation in motor designs with higher-strength low-loss ES grades. Therefore, thermal analysis becomes crucial for a better estimation of the energy saving. In order to prove this concept, a coupled electromagnetic-mechanical-thermal finite element (FE) model has been built. Firstly, the optimal bridge thickness of the V-shaped IPM rotor is estimated by evaluating the von Mises stress at the maximum operating speed using a static structural analysis. Then the stator current is optimized by iterative computations of transient electromagnetic and lumped-parameter thermal models at rated operation conditions. This paper illustrates that the utilization of higher-strength low-loss ES grades results in up to 7% temperature reduction which leads to 8% energy saving and/or a significant reduction of rare-earth permanent magnet (up to 5.4%) depending on the designers' main interest.","PeriodicalId":297228,"journal":{"name":"2022 12th International Electric Drives Production Conference (EDPC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134280450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Impact of Electric Vehicle Charging Behavior on the Transmission System and the Electricity Market in Germany","authors":"Franz Teske, Felix Funk, Adrian Fehrle, J. Franke","doi":"10.1109/EDPC56367.2022.10019754","DOIUrl":"https://doi.org/10.1109/EDPC56367.2022.10019754","url":null,"abstract":"The increasing market penetration of electric vehicles (EVs) not only creates challenges at the lower voltage levels of the power grid but also significantly impacts the national energy system. The latter effect is, however, rarely discussed in current research, which primarily focuses on the integration of EVs into the distribution grid. This paper, therefore, examines the impact of defined EV penetration levels and user behaviors on the national transmission grid and wholesale electricity prices. For this purpose, a fundamental model of the German power system, consisting of the loads, the power plants, and the transmission grid, is created. This model is then used to simulate and analyze the impact of selected charging behaviors. It is shown that wholesale electricity prices and transmission grid utilization hardly depend on the chosen hourly charging profile of EVs. Rather, the maximum power and the amount of electricity are the most significant influences. Additional load leads to a small increase in the electricity price, but not to an aggravation of line congestion problems.","PeriodicalId":297228,"journal":{"name":"2022 12th International Electric Drives Production Conference (EDPC)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133459809","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Johannes von Lindenfels, Mohammad Pahlevani Qomi, Daniel Utsch, J. Franke, A. Kühl, Lukas Reißenweber, Alexander Stadler
{"title":"Electromagnetic Actuators Suitable for High Temperatures Using Thin Aluminum Foil as Conductor","authors":"Johannes von Lindenfels, Mohammad Pahlevani Qomi, Daniel Utsch, J. Franke, A. Kühl, Lukas Reißenweber, Alexander Stadler","doi":"10.1109/EDPC56367.2022.10019743","DOIUrl":"https://doi.org/10.1109/EDPC56367.2022.10019743","url":null,"abstract":"Electromagnets are widely used as drive elements in many technical areas, e.g. as control elements for valves. The technical requirements include, for example, static and dynamic electromagnetic properties, compact design and reliability. On the economic side, the total costs must be considered. Copper (Cu) is predominantly used as a conductor material for electromagnets. However, this is problematic due to the fluctuating market prices of the metal. For example, the raw material prices for Cu have doubled somewhat between 2016 and 2022. In this paper, as an alternative to coils made of round Cu wire, options are sought for producing coils from anodised aluminum (AI) foil. For this purpose, the advantages and disadvantages of round Cu wire and Al foil are discussed with regard to material properties, manufacturing processes and handling. First, technical concepts for the realisation of this replacement are reported. Then the cylindrical coil is manufactured from anodised Al coil and a prototype of a cylindrical coil is built for demonstration. The newly manufactured coils are tested against the conventional coils made of Cu and the results of the comparison are presented.","PeriodicalId":297228,"journal":{"name":"2022 12th International Electric Drives Production Conference (EDPC)","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127540137","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Investigation of Ceramic-coated Profile Conductors Regarding Insulation Strength with the Aim of Better Thermal Connection to the Laminated Core of Electrical Machines","authors":"C. Weber, Florian Liebetrau","doi":"10.1109/EDPC56367.2022.10019762","DOIUrl":"https://doi.org/10.1109/EDPC56367.2022.10019762","url":null,"abstract":"This work addresses an alternative approach to electrical insulation of the winding by using ceramic materials such as aluminum oxide, which in addition to good insulation strength also have relatively high thermal conductivity. This can be applied to copper by thermal spray processes, which also allow the use of profiled conductors. In the present work, the determined values for insulation strength and insulation resistance are presented depending on different layer thicknesses and manufacturing parameters, as well as the influence of post-treatments. For this purpose, a special measurement setup is used which records the corresponding data with a large number of contact points and thus takes into account weak points caused by manufacturing variations.","PeriodicalId":297228,"journal":{"name":"2022 12th International Electric Drives Production Conference (EDPC)","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124246271","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Kampker, H. Heimes, Fabian Schmitt, Till Backes, Michael D. Betz, Tarik Hadzovic
{"title":"Design of an Electric Drive Axle for Heavy Duty Commercial Vehicles in the Long-Haul Application Under Consideration of Energy Consumption","authors":"A. Kampker, H. Heimes, Fabian Schmitt, Till Backes, Michael D. Betz, Tarik Hadzovic","doi":"10.1109/EDPC56367.2022.10019741","DOIUrl":"https://doi.org/10.1109/EDPC56367.2022.10019741","url":null,"abstract":"In order to meet the challenge of electrification of heavy commercial vehicles with up to 41 t gross vehicle weight restriction, one possible promising approach is the development of a modular electric powertrain kit. In the following analysis, an integrated electric drive axle is designed for a 41 t tractor-trailer-unit in long-haul transport as part of a modular drive system with an integrated fuel cell. The lay out design begins with selected static driving profiles from which the requirements, such as the maximum drive torque and power, are derived for the drive axle. Subsequently, a concept with two permanent magnet synchronous motors and different gear stages is being analysed. In a parameter study, a simulation of the drivetrain in different driving cycles shows how a possible length variation of the motors and the change from a single- to a two-speed gearbox contribute to optimal energy efficiency and thus to lower energy consumption in the selected cycles. Furthermore, the existing conflict of objectives between motor and transmission package is addressed.","PeriodicalId":297228,"journal":{"name":"2022 12th International Electric Drives Production Conference (EDPC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130939439","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Inductance Evaluation and Average Torque Separation of Externally Excited Synchronous Machines Using Frozen Permeability","authors":"Samar Singh, M. Doppelbauer","doi":"10.1109/EDPC56367.2022.10019742","DOIUrl":"https://doi.org/10.1109/EDPC56367.2022.10019742","url":null,"abstract":"This paper investigates an externally excited synchronous machine (EESM), designed for traction application, regarding the calculation of its absolute inductances and the determination of its average torque constituents. In order to compute the torque components precisely, the magnetic field density produced in the EESM is resolved into individual components corresponding to the different sources of excitation, namely the d-axis, the q-axis and the rotor field current. The frozen permeability (FP) method is employed to compute these magnetic field density components enabling the computation of the flux linkage produced by each source of excitation individually. Subsequently, self, mutual and cross-coupling inductances of the EESM are calculated in the dq-frame as a function of stator and rotor currents. Finally, using the absolute inductance values the different torque components, namely the Lorentz (excitation) torque, the reluctance torque and the cross-coupling torque, are also evaluated as a function of stator and rotor currents. The torque maps are presented at discrete rotor excitation levels to understand the movement of the maximum torque per ampere (MTPA) line with respect to the d-axis and q-axis currents, for different field current values. The results discussed in this paper also provide an insight into the difference between the impact of the reluctance torque on the total torque of salient pole permanent magnet synchronous machines (PMSMs) and EESMs.","PeriodicalId":297228,"journal":{"name":"2022 12th International Electric Drives Production Conference (EDPC)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115376633","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Weiss Hannes Alois, Stauble Thomas, Gilch Ines, Senn Georg, Weber Thomas Michael, Bohm Lucas, G. Pasquarella, Volk Wolfram
{"title":"Modified magnetic properties due to roller leveling of electrical steel","authors":"Weiss Hannes Alois, Stauble Thomas, Gilch Ines, Senn Georg, Weber Thomas Michael, Bohm Lucas, G. Pasquarella, Volk Wolfram","doi":"10.1109/EDPC56367.2022.10019756","DOIUrl":"https://doi.org/10.1109/EDPC56367.2022.10019756","url":null,"abstract":"When processing stator and rotor cores from electrical steel strip material, different processing steps induce additional mechanical stress resulting in deteriorated magnetic properties. They can originate from heating process induced thermal strains or plastic deformation process induced mechanical strains. Due to its impact on magnetic material properties, such process-related deteriorations must be considered when developing an electrical machine. With regards to blanking, a high-volume production process, different manufacturing steps, i.e. punching, blanking, forming and interlocking, can induce plastic deformation. One process often neglected is roller leveling. This process sometimes is necessary to enable complex lamination geometries for rotor, stator or both to be cut from an electrical steel strip. Especially, for magnetic cores that get bigger in diameter and therefore stamping tools that increase in length, using roller leveling to produce flat parts becomes inevitable. Within the presented study electrical steels varying in its manufacturer, its batch and its thickness are roller leveled to different levels of plastic deformation. The increasing mechanical stress' impact on magnetic properties like specific iron loss is discussed regarding different frequencies and polarizations. Overall, the study proves that roller leveling is a process one might consider twice before using it to produce top-notch electrical machines.","PeriodicalId":297228,"journal":{"name":"2022 12th International Electric Drives Production Conference (EDPC)","volume":"133 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127328478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}