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Cardiovascular diseases, including congenital and acquired cardiovascular diseases, impose a severe burden on healthcare systems worldwide. Although bone marrow-derived stem cells (BMSCs) therapy can be an effective therapeutic strategy for the heart disease, relatively low abundance, difficult accessibility, and small tissue volume hinder the clinical usefulness. Adipose tissue-derived stem cells (ADSCs) show similar potential with BMSCs to differentiate into lineages and tissues, such as smooth muscle cells, endothelial cells, and adipocytes, with attractiveness of obtaining adipose tissue easily and repeatedly, and a simple separation procedure. We briefly summarize the current understanding of the cardiomyocytes differentiated from ADSCs

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.

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.

This paper introduces a novel double stator switched reluctance machine (DSSRM). U-shaped stator blocks are used for both internal and external stators. Each stator tooth is wound with a central winding, and the polarities of the two stator teeth on each U stator block are opposite. Firstly, the working principle and the geometric design of the proposed DSSRM are given. The methods of reducing torque ripple from machine structure of the proposed DSSRM are illustrated. Then, this paper makes the comprehensive comparison between conventional DSSRM and proposed DSSRM by finite element method (FEM). The simulation results indicate that this proposed DSSRM has lower torque ripple and higher torque density than the conventional DSSRM. Finally, a prototype motor is manufactured and the simulation analysis is validated by the experimental results.

The eddy-current loss of switched reluctance motor (SRM) is studied and analyzed in this paper. As a significant part of core loss, eddy-current loss has a great influence on motor performance. First, the average magnetic flux waveforms in every distributed region are derived from the magnetic equivalent circuit (MEC) model. Based on this, each harmonic of magnetic density is obtained by adopting the fast Fourier transform (FFT) method for further calculation. Then, each harmonic eddy-current loss is computed by sinusoidal magnetic density and the total eddy-current loss in different region of motor is derived by superposing of them. Therefore, the calculated results at different speed and conduction angles of each region are analyzed. Finally, the 3D finite element (FE) model is established in software FLUX and the experimental platform of the SRM prototype is built.

To overcome the disadvantages of traditional switched reluctance machine (SRM) with moderate power/torque density and high torque ripple, this article proposes a novel double-stator SRM (DSSRM) with the inner and outer stators both adopting U-shaped segmental stator structure. By optimizing the polarity distribution of the inner and outer stator magnetic fields, the inner and outer stator magnetic fields are decoupled. Then, the relationships of torque ripple coefficient with the mechanical offset angles of the inner and outer rotor teeth are investigated. To optimize the mechanical offset angle and reduce the torque ripple of the motor, the initial design method is proposed, and five main parameters of the machine are optimized by the finite-element analysis. Then, the static magnetic characteristics and dynamic performance of this novel machine are simulated and analyzed. Finally, a 16/18/18/16 DSSRM is prototyped to validate the above simulation and theoretical analysis.

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.

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.

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.

This paper gives a way to analyze the flux characteristic of a single-phase tubular permanent magnet linear motor (TPMLM) based on the 3-D magnetic equivalent circuit (MEC) method. By studying the flux tubes of this single-phase TPMLM with the finite-element analysis software—FLUX, a 3-D MEC model of this motor can be constructed, and the flux linkage of the single-phase TPMLM can also be calculated. The static and dynamic performances of the single-phase TPMLM calculated with the 3-D MEC model are compared with the 3-D finite-element model and experimental results, which verify the correctness of the proposed 3-D MEC model.

In this study, the design optimisation of a switched reluctance machine (SRM) with the layered method has been studied. Firstly, a multi-physical analytical model for the SRM is established. The proposed model consists of an electromagnetic model, an electrical model, a loss model, and a thermal model. Then a layered optimisation design method suitable for the SRM is proposed in combination with the multi-physical field simulation model. Taguchi method is used to analyse the influence degree of the main geometric dimensions on the dynamic performance, and the parameters are divided into high-sensitivity parameters (HSPs) and low-sensitivity parameters. The non-dominated sorting genetic algorithm-II algorithm is used to optimise the HSP by the proposed model. The iron loss, average torque, average torque per unit mass, torque ripple and efficiency are taken as the objective functions. Finally, the prototype is manufactured and a testing platform is built. The flux linkage of several special positions of the machine is verified experimentally, and the accuracy of the electromagnetic model in the multi-physical field model is verified. The temperature experiments are carried out on the machine, and the accuracy of the equivalent heat circuit model in the multi-physical field model is verified.

Purpose An improved simulation model of switched reluctance motor (SRM) for steady-state operation that considers the core losses in the stator and rotor is established to obtain the steady performance of the high-speed SRM during the design, analysis and control of SRM driving system more accurately. Design/methodology/approach The transient core loss model for the material and SRM is presented. Then a new method for calculating the flux density of the motor in real time is introduced, and a steady-state simulation model of the SRM including real-time transient core losses calculation model is established according to the transient flux density. Because the transient core losses calculated by above method are the total core losses of the motor, a core losses distribution method is proposed and the steady-state simulation model of the SRM including the distributed core losses’ effect on the phase winding is established. Findings The comparison results show that the proposed model has higher accuracy than the traditional model, excluding core losses, especially at the moments when phase voltage is turn-on and turn-off. The proportion of the core losses to the motor losses increases with the increase in speed. So, the core losses’ effect on the steady-state performance of the high-speed SRM cannot be ignored. Originality/value The method to obtain flux density in the real time is presented and the improved steady-state simulation model of SRM that considering transient core losses is proposed.

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.

In this paper, a novel double stator switched reluctance machine (DSSRM) is proposed, which combines the characteristics of the magnetic circuit of the U-type stator modular switched reluctance machine (SRM). By optimizing the polarity distribution of the motor, the magnetic field produced by the inner and outer stator windings can be decoupled, so that the inner and outer stator windings can be controlled separately. On this basis, it is proposed that the center line of the inner and outer teeth of the rotor be staggered at a certain mechanical angle. To optimize the mechanical angle of the motor and reduce the torque ripple of the motor.

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.

This study sets forth an equivalent electric circuit (EEC) model including core losses and phase interactions to obtain a more accurate steady and dynamic performance of the high speed switched reluctance motor (SRM) during the design, analysis, and control of the SRM drive system. The magnetic equivalent circuit (MEC) method is used to calculate the flux linkage and torque quickly and relative accurately. Based on the principle of transformation between the MEC and EEC, the EEC model is derived from the MEC model. To enhance the model precision, the dynamic core losses and phase interactions are analysed and added to the EEC model. The relationship between the phase current and virtual current corresponding to different parts is deduced. Then the simulation model of the whole SRM driver systems is established in MATLAB/Simulink to obtain the phase current and virtual current corresponding to a different portion. The experimental and simulated results of the static MEC model and the whole SRM drive system including the EEC model provide the conclusive evidence for validating their practicability.

To model the nonlinear characteristic of the flux linkage for the switched reluctance motor, a modified flux linkage analytical model and a fast model are proposed. The models are based on an original polynomial model which fits the ψ - θ curve at different phase currents by analyzing the error percentage curve of the original model in this paper. The coefficient of the polynomial is discussed for a fast model in order to solve the modeling problems quickly. Then, the electromagnetic torque of switched reluctance motor is calculated by the modified model and the fast model, which agree well with the finite element results. Based on the modified model, the simulation model is built in MATLAB/Simulink. Also, an experimental platform is established to validate the proposed models.

This paper introduces a novel 16/12 outer module rotor-type switched reluctance machine. Unlike conventional structures, the proposed rotor structure includes some discrete module, and every outer module rotor is U-shaped structure and has two rotor poles. Each phase winding is composed of two series coils wrapped on two stator teeth. The short flux lines can be generated by excited adjacent phase and use the U-shaped module rotor. The module rotor can also decrease the mass of the rotor. The proposed U-shaped structure machine can enhance the electrical utilization, decrease the magneto motive force requirement, and reduce the iron loss compared with the conventional machine. The operation and design principle of the proposed U-shaped structure machine are illustrated and elaborated to verify the machine operation performance. The static and dynamic performance of the proposed U-shaped structure 16/12 outer rotor machine and conventional machine is obtained by the finite-element method. The effectiveness and availability of the proposed U-shaped structure outer rotor machine are confirmed by the simulation results.

Purpose This paper aims to establish a modified variable coefficient calculation model to analyse the control parameter effect on the iron loss of switched reluctance motor under pulse width modulation (PWM) mode. Design/methodology/approach The finite element model is solved to get the flux density by python language. Due to non-sinusoidal flux density feature and the effect of PWM excitation, the Fourier transform is applied in consideration of harmonic components. To improve the accuracy of iron loss computation, the effect of minor loops is considered by using the rain-flow counting method. Findings When the speed fluctuates around the set speed and the fluctuations are relatively small, it is useful to reduce the iron loss with smaller duty ratio and turn-on angle or greater duty ratio and smaller turn-off angle. The iron loss is less affected by chopping frequency, while the iron loss increases obviously with higher conduction angles. The iron loss under non-energy-returnable-voltage-chop mode is greater than energy-returnable-voltage-chop mode. Originality/value The modified variable coefficient MIEM5 iron loss model is proposed to improve the accuracy of iron loss calculation. Then the control parameters such as duty ratio, chopping frequency, turn on angle and turn off angle are analysed under PWM mode.

Tubular switched reluctance linear motor (TSRLM) has lower loss and higher thrust density than flat-type switched reluctance linear motor. Two kinds of single-phase TSRLMs with different surrounding magnetic flux paths are introduced in this paper. The structure of transverse flux TSRLM (TF-TSRLM) is compared with the structure of the longitudinal flux TSRLM (LF-TSRLM). The structure selection of TF-TSRLM with two poles, four poles, six poles, and eight poles is made for enhancing average electromagnetic thrust. The comparisons between LF-TSRLM and TF-TSRLM are made in the same stator outer diameter, the same mover laminated thickness, and the same excited current on static electromagnetic thrust, magnetization curves, average thrust per unit volume, and average thrust per unit mass. They show that the TF-TSRLM with the six-pole structure is considered as a relatively more reasonable structure for enhancing the space effective utilization rate and increasing the electromagnetic thrust.

This study analyses the influence of the control parameters on the iron loss of the switched reluctance motor under different control modes by using the motor iron loss model which is suitable for different control modes. The motor iron loss model combines the magnetic equivalent circuit (MEC) method with the finite element (FE) method. First, the static flux density of the motor is obtained by the FE software, and then the relationship between the characteristics of static flux density and dynamic flux density is analysed through the MEC method. In combination with the motor dynamic MATLAB/Simulink model, the dynamic flux density of different feature regions is obtained. Simultaneously, the iron loss model of the motor is established in MATLAB/Simulink according to the loss model so that the motor loss can be calculated rapidly and accurately. Then, the influence of the control parameters on the motor loss is calculated and analysed under angle position control and current chopping control. The accuracy of the loss model and analysis results are verified by experiments.

This paper studies about the influence of different polarity distribution on the iron loss and temperature field on a four-phase 8/6 structure switched reluctance machine for electric vehicles. Firstly, a switched reluctance iron loss mathematical calculation model is proposed by fitting the core silicon sheet iron loss data of the prototype. Then, a 2D finite element model is constructed to analyze the magnetic flux density waveforms of iron core. Magnetic flux densities of the iron core under two different magnetic poles distributions are also compared. The iron loss of the different magnetic pole distribution is calculated respectively. Finally, the 2D finite element thermal model of the prototype is established and the simulation results are analyzed. Then, the experimental test platform is built. The experimental results show that the temperature rise is in good agreement with the simulated temperature rise.

Recent studies have demonstrated that dysregulation of mircoRNAs (miRNAs) greatly affected biological processes of human cancers, including colorectal cancer. As a member of miRNAs family, miR-873-5p has been proved to be a tumor suppressor in some human cancers. Here, we aim to investigate the effects of miR-873-5p on the migration, invasion and epithelial-mesenchymal transition (EMT) of colorectal cancer cells. The low expression of miR-873-5p in colorectal cancer cells was identified by conducting qRT-PCR analysis. Gain of function assays were designed and conducted to demonstrate the specific function of miR-873-5p overexpression in colorectal cancer progression. Transwell assay and western blot assay were conducted and revealed that miR-873-5p inhibited cell migration, invasion and EMT formation. To find the downstream molecular mechanism of miR-873-5p, mechanism assays were designed and performed to find the downstream target of miR-873-5p. ZEB1 (Zinc finger E-box-binding homeobox 1) was certified to be the target of miR-873-5p through bioinformatics analysis, luciferase activity assay and pull-down assay. Finally, rescue assays were carried out to demonstrate the effects of miR-873-5p-ZEB1 axis on the migration, invasion and EMT process of colorectal cancer cells. In conclusion, we confirmed that miR-873-5p suppressed cell migration, invasion and EMT in colorectal cancer via targeting ZEB1.