The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
This paper proposes a novel dc-excited flux-modulated linear machine with a new primary structure for utilizing amorphous core. Although amorphous core is regarded as a good candidate in highly efficient electric machines, and is being investigated for decades, it has not been widely used in electric machines yet. The key challenge is the difficulty in slotting. For the new structure, the difficulty...
This contribution suggests an approach to determine the optimal design of a Permanent Magnet Synchronous Motor for a given application by calculating the effects of coil configuration switching, pole-changing and multi-phase windings. The impact on the torque-speed-characteristic of a motor is evaluated in a normalized parameter plane, enabling the designer to compare the influences by using criteria...
This paper is focused on the analysis of the geometrical deviation of a variable reluctance (VR) resolver and its impact to the inverter losses for automotive applications. Therefore a VR resolver model is introduced, verified with measurements at a sensor test bench and the additional inverter losses are investigated.
This paper presents a set of system equations of a dual stator induction machine (DSIM) and a new approach for online parameter identification including its verification through simulation and measurements. An uneven current share between the two three-phase systems of a DSIM is used to determine machine parameters online.
During the first decade of the 1900s, 38 percent of all cars in the United States ran on electricity, a share that declined to practically zero as the internal combustion engine rose to dominance in the 1920s. Today's drive to save energy and reduce pollution has given the electric car new life, but its high cost and limited range of travel combine to keep sales figures low.
The design of superconducting machines requires a knowledge of the magnetic characteristics of non-oriented soft magnetic materials at low temperatures. Therefore the performance of the electrical steels has to be examined under the given temperature constraints. This report shows that operating the steel at low temperature leads to increased iron core losses and an increased relative permeability...
This paper presents a holistic approach to determine the effect of online reconfiguration of the motor winding of a synchronous permanent magnet motor resulting in switching the number of turns. The analysis is based on a parameter plane, which predicts the behavior of synchronous machine designs by using only two normalized parameters, the permanent magnet flux linkage and the ratio of the quadrature...
Rotor and stator stacks consist of laminated electrical steel sheets and represent the essential components of an electric drive. The process chain for the production of laminated stacks comprises two core steps: first, the separation of the final contour of the electrical sheets and, second, the joining of individual sheets to a laminated stack. Both steps can be executed by different technologies...
Variable reluctance resolvers are needed to regulate electrical machines with inverter control. Due to several issues, e.g. discrete windings in the stator and geometric tolerances in the assembly of the electrical machine, the rotors angular position cannot be acquired properly. The subject of this paper is a variable reluctance resolver model to investigate manufacturing induced geometrical tolerances...
This paper presents a novel control scheme for any kind of electrically or hybrid excited synchronous machine with an additional rotor excitation winding. Using a generalized machine model, the proposed method offers highly dynamic and precise machine control. The theoretical background on this approach as well as measurement results of a hybrid excited machine prototype with displaced reluctance...
In this paper the fundamental knowledge of a variable reluctance resolver is presented and an analytical model is demonstrated. With the simulation results are calculated and validated by measurements on a sensor test bench. Based on the introduced model, mechanical and electrical failures of any variable reluctance sensor can be analyzed. The model based simulation is compared to the measurement...
A holistic approach to determine the optimum number of phases m of an m-phase motor in combination with an m-leg inverter for electric vehicle applications is presented. The optimum offers a significant improvement of the torque and power by approximately 9.6% over the whole operating range in comparison to a 3-phase motor and therefore enhances the power and torque density without expanding the design...
Iron losses are an important issue in high speed switched reluctance motors. A tool chain for the analysis of iron losses is introduced where arbitrary control schemes can be applied and a two-dimensional local loss distribution can be derived. The results are compared to a conventional calculation where individual machine components of uniform flux distribution in either tangential or radial direction...
Switched reluctance motors are a promising low cost alternative for electric vehicles. The most promising stator pole / rotor pole configuration for high rotational speeds is often being discussed. In this work, Pareto sets of SRM designs are generated with respect to efficiency and maximum power density in order to provide a basis for the decision of the most promising pole configuration at different...
This paper presents a novel hybrid permanent magnet and wound field synchronous machine geometry with a displaced reluctance axis. This concept is known for improving motor operation performance and efficiency at the cost of an inferior generator operation. To overcome this disadvantage, the proposed machine geometry is capable of inverting the magnetic asymmetry dynamically. Thereby, the positive...
This paper presents the design and analysis of a high-speed induction machine with a die cast copper squirrel cage used as traction drive in an electrical vehicle. Herby the drive performance of the machine in combination with a three gear shift gearbox is described. Great attention is paid to the mechanical design and the necessary simulations to ensure save operation of the machine at maximum speed...
This paper examines the possibility of protecting the magnets of permanent magnet electrical machines against demagnetization in case of a sudden three-phase short circuit at the terminals of the stator winding. An analytical description of the effects that reduce the load that can demagnetize the permanent magnets is provided and verified using FEM simulation.
This paper examines the demagnetization of magnets of permanent magnet excited electrical machines in the case of a sudden three-phase short-circuit at the terminals. An analytical approach is applied and an FEM simulation is performed, and the results are compared for validation.
Based on Schwarz-Christoffel mapping and Maxwell stress tensor, new analytical formulas to calculate the torque of the SRM and DSPMM are derived. Through the new expression, it is easy to understand the relationship between the torque and the design parameters of the machine. Additionally, the force distribution on the rotor tooth contour is presented. By using the torque formulas, the torque densities...
To further improve the power density of modern electric drive technologies many motor designers decide to increase the rotational speed of the motor up to several tens of thousands revolutions per minute. Along with these high frequencies of the fundamental wave of the flux density inside the laminated stator cores, the electromagnetic strain of the core and the importance of the iron losses are increasing...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.