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This article investigates the design methods and performance optimization of segmented-double-stator switched reluctance machine (SDS-SRM). First, two segmented U-shaped single-stator SRMs are introduced, including inner-rotor and outer-rotor constructions. In order to enhance the torque and power density, these two kinds of single-stator SRMs are combined together to constitute an SDS-SRM. Then, the relationships of torque ripple coefficient with the mechanical offset angles of the inner and outer rotor teeth are investigated to obtain the optimal rotor structure, and the corresponding conduction phase sequences for double-stator excitation mode are also analyzed. Furthermore, the flux distributions of the inner and outer stators with different coil magnetic polarities configurations are researched, and it reveals that the phase windings both on inner and outer stators with NSSNNSSN polarities have better magnetic field decoupling characteristics. To evaluate the final topology of the proposed SDS-SRM, the static magnetic characteristics and dynamic performances are presented. Finally, the SDS-SRM prototype is manufactured and tested to validate the theory and simulation analyses. [ABSTRACT FROM AUTHOR]

This paper mainly takes a 6/4 switched reluctance motor (SRM) as an example to analyze the temperature of the motor. In order to establish the equivalent thermal circuit model (ETCM) conveniently, the mechanical structure of the motor is simplified to a certain extent, and the characteristic nodes are divided. Then the heat transfer process in the rotor region, the stator region and the whole motor during the operation of the motor is analyzed, and the ETCM of those regions are established respectively. This method of establishing ETCM is also applicable to superconducting motors. Based on the basic principles of heat transfer, the calculation method of thermal resistance in each ETCM is given in this paper. Then, the three-dimensional (3-D) finite element (FE) temperature field model of the motor is built and compared with the ETCM. Finally, the accuracy of the ETCM is verified by experiments. [ABSTRACT FROM AUTHOR]

Based on a four‐phase 8/6 structure switched reluctance machine for electric vehicles, the influence of different magnetic pole distributions on iron loss and temperature field is studied here. Firstly, by fitting the core silicon sheet iron loss data of the prototype, a mathematical calculation model of switched reluctance iron loss is constructed. Then, in order to analyse the flux density waveform of the iron core, a 2D finite element model is proposed. Under different magnetic pole distributions, the magnetic flux densities of the iron core are compared and the iron loss is calculated as well. Finally, the simulation results are obtained by establishing the 2D finite element thermal model of the prototype and analysed. Then, the experimental test platform is built and experimental data are recorded and analysed. By comparing the experimental results, it is found that the temperature rise is well consistent with the temperature rise of the 2D finite element thermal model. [ABSTRACT FROM AUTHOR]

This paper analyzed the flux characteristics of a single-phase tubular switched reluctance linear motor (TSRLM) based on magnetic equivalent circuit (MEC) method. The single-phase TSRLM is divided into five different parts, which are the teeth of the stator, the yoke of the stator, air gap, the teeth of the mover, and the yoke of the mover. The reluctance of every part is expressed in analytical formulas at five special mover positions. The flux linkages at five special mover positions are calculated by magnet tube method and Gauss–Seidel iteration method which takes the saturation into consideration. A high-order Fourier series method is used to map the nonlinear relationship between flux linkage, current, and mover position with the flux linkage data calculated by the MEC method. The calculated flux linkage is consistent with 3-D finite-element method and experimental results. The dynamic and static performance of the simulation utilized with MEC method is consistent with those in experiments, which verifies the accuracy of the MEC method proposed in this paper. [ABSTRACT FROM AUTHOR]

The iron loss of doubled-sided linear switch reluctance motor (DLSRM) is analyzed and calculated in this paper. Because of the double salient structure of the switched reluctance motor and the nonlinearity of the magnetization curve of the ferromagnetic material, the flux density waveform is nonsinusoidal. So, it is difficult to calculate the iron loss of DLSRM. This paper mainly introduces the calculation method of dynamic magnetic density of the DLSRM, and basing on this, the simulation model of iron loss of DLSRM is built and compared the iron loss in different parts of the total as a percentage of the motor. Finally, an experimental platform based on DLSRM is built to measure the actual iron loss in the motor and verify the correctness of the calculation of iron loss. [ABSTRACT FROM AUTHOR]

This paper analyzes the flux characteristics and normal force of the double-sided switched reluctance linear machine (SRLM) under the asymmetric air gap. The magnetic equivalent circuit (MEC) of the machine and the details of the flux paths configuration at six distinct mover positions under the asymmetric air gap are included. Then, six special mover position magnetization curves are calculated by solving the MEC with the method of Gauss–Seidel. The magnetic flux-linkage model and thrust model based on six distinct mover positions are established by analytical polynomial. Three-dimensional (3-D) finite-element method (FEM) simulation and the experimental study with the prototype hardware are carried out to validate the accuracy of the MEC model calculated for the flux linkage and normal force. The six distinct mover positions flux linkage and normal force calculated by the MEC are consistent with the 3-D FEM calculated data and experimental data. It indicates that the proposed method to calculate the flux linkage and the normal force is feasible and effective. The dynamic analysis is also conducted. The simulated phase current waveforms are also consistent with the experimental results. It indicates that the presented method can be used to simulate the phase current under the asymmetry air gap effectively. The normal force under different asymmetry rates is analyzed, which provides the theoretical basis for reducing the unbalanced force of the double-sided SRLM. [ABSTRACT FROM AUTHOR]

This paper proposes a novel multiobjective optimization design method for a switched reluctance motor (SRM) on low-speed electric vehicles (EVs). According to the indexes of a low-speed EVs propulsion system and the large torque ripple of the SRM, six objectives of geometric parameters optimization of the SRM are given, which are maximum speed, acceleration time (including in situ acceleration time and overtake acceleration time), maximum climbing gradient, energy usage ratio, and torque ripple factor. The rated parameters of the driving motor are given based on the basic parameters of the low-speed EVs. Based on the engineering design method, the dimension range of the SRM under the rated parameter range is confirmed. The dynamic simulation model of a low-speed pure EVs propulsion system is built in MATLAB/Simulink based on the finite element model of the SRM and the vehicle balance equation. Then, a multiobjective optimization design of the geometric parameters of the SRM is carried out by a Taguchi–chicken swarm optimization algorithm. The correctness of the finite element model is verified, and the accuracy of the multiobjective optimization is verified by the dynamic simulation results and the low-speed EV experiment. [ABSTRACT FROM AUTHOR]

A fast method to calculate the iron loss of switched reluctance motor (SRM) is proposed. The key of the method is that the flux density waveforms in different parts of the motor can be obtained quickly. First, the static flux density data varying with phase current and rotor position in various parts of SRM are obtained by finite element method (FEM). Then, the static flux density data are stored in 2D look‐up tables in Matlab/Simulink to get the flux density waveforms by look‐up table method, and the obtained flux density waveforms are verified by FEM results. Since the flux waveforms are non‐sinusoidal and non‐linear, an accurate and fast model for the iron loss prediction is presented, and different modified factors are applied to calculate the hysteresis loss according to the classification of flux density waveforms. Based on that, the calculation model is established in Matlab/Simulink, and iron losses of a three‐phase 6/4 structure SRM under different turn‐on and turn‐off angles and load conditions are calculated and analysed. Finally, measured results are presented to verify the precision of the calculation model. [ABSTRACT FROM AUTHOR]