Reluctance Motor For Electric Vehicles Research Articles

Direct Torque Control of a Four-Phase Switched Reluctance Motor for Electric Vehicle Drives

Direct Torque Control of a Four-Phase Switched Reluctance Motor for Electric Vehicle Drives

A Novel Interturn Fault Tolerant based Average Torque Control of Switched Reluctance Motors for Electric Vehicles

A Novel Interturn Fault Tolerant based Average Torque Control of Switched Reluctance Motors for Electric Vehicles

Optimum design and research of switched reluctance motor for electric vehicle based on Motor-Cad

With the development of the economy and the deepening of the energy crisis, electric vehicle has now become the hotspot of the global automotive industry. Therefore, as the key part of electric vehicle, the design and research of drive motor has become the focus of attention of engineers and technicians. Because of its simple structure, easy maintenance, high output power, high output torque, wide speed range, and high efficiency, the switched reluctance motor (SRM) has been one of the first choice of electric vehicle driving motors. According to the performance requirements of electric vehicle driving motors, a 3-phase 24/16 pole with rated power of 30 kW switched reluctance motor (SRM) for electric vehicle has been designed in this paper by using Motor-Cad which can be used to optimize the parameters of motor to make the overall structure of the motor more reasonable. In order to reduce the torque ripple of switched reluctance motor, appropriate stator polar arc and rotor polar arc design are used in the motor. To realize the speed control of switched reluctance motor in a wide range, PWM control mode is adopted in this paper, which has fast motor response speed, high power factor and excellent dynamic and static performance. The simulation results show that the performance indexes of the switched reluctance motor meet the design requirements completely.

Torque Ripple Suppression of Synchronous Reluctance Motors for Electric Vehicles Based on Rotor Improvement Design

Torque Ripple Suppression of Synchronous Reluctance Motors for Electric Vehicles Based on Rotor Improvement Design

Design and Double-Stage Optimization of Synchronous Reluctance Motor for Electric Vehicles

In this study, a high-power synchronous reluctance motor (SynRM) was designed for the traction motor of electric vehicle (EV) and its double-stage optimization was performed. Genetic algorithm and sensitivity analysis methods were used to obtain the best design parameters. Double-stage optimization was carried out to minimize the torque ripple and obtain the targeted torque, speed, and power values of the SynRM. In the first stage, the genetic algorithm method was used to improve the design parameters of the stator and rotor. With the improved design parameters, it was observed that the torque ripple decreased. In the second stage, the sensitivity analysis method was used. In this method, the effect of changing the skew angle of the stator on the torque ripple was investigated. The performance of the designed motor was examined in the optimization process. It was observed that the targeted torque, power, speed, efficiency, and torque ripple minimization values are successfully achieved with the best stator and rotor parameters. The results showed that SynRM produces high torque and high power with high efficiency and low torque ripple over wide speed range. It is quite proper to use the designed SynRM as a traction motor of new generation electric vehicles.

A Novel Universal Torque Control of Switched Reluctance Motors for Electric Vehicles

Due to their advantages, switched reluctance motors (SRMs) are interesting solutions for electric vehicle (EV) propulsion. However, they have the main drawback of high torque ripple. This paper develops a universal torque control (UTC) technique for SRM that can fulfill all vehicle requirements under a wide range of speeds. The developed UTC involves two different control techniques. It utilizes the direct instantaneous torque control (DITC) strategy in a low speed region, and the average torque control (ATC) strategy in high speeds. The selection of DITC and ATC is made based on their performance regarding torque ripple, torque/current ratio, and efficiency. Moreover, a novel transition control between the two control techniques is introduced. The results show the ability of the proposed UTC to achieve vehicle requirements while obtaining all the benefits of torque control over the possible range of speeds. The proposed UTC provides the best performance regarding minimum torque ripple, maximum torque/current ratio, and maximum efficiency over the whole speed range. The transition control achieves a smooth operation without any disturbances. The transition control helps to simplify the overall control algorithm, aiming to have a feasible and practical UTC without a complicated control structure.

Analysis and Comparison of Operational Characteristics of Electric Vehicle Traction Units Combining Two Different Types of Motors

This paper proposes a traction unit that combines an interior permanent magnet motor and a PM-assisted synchronous reluctance motor for electric vehicles to improve traction performance, enhance energy efficiency, and reduce cost. The characteristics of three traction units are analyzed and compared, including (a) rear-wheel-drive configuration using one IPM motor; (b) all-wheel-drive configuration using two interior permanent magnet motors; and (c) all-wheel-drive with a combination of one interior permanent magnet motor and one PM-assisted synchronous reluctance as proposed in this paper. The operational characteristics of each motor to achieve a wide constant power speed range are first investigated. Then, the Urban Dynamometer Driving Schedule is utilized to compare and evaluate the operational characteristics, energy consumption, and most importantly, the efficiency of the traction units. Simulation results reveal that the overall efficiency of the proposed traction unit can be improved compared to the other configurations. The advantages and drawbacks of the proposed traction unit are also investigated. Finally, experiments are conducted to validate the analysis.

Investigation of an Outer Rotor In-Wheel Switched Reluctance Motor for Electric Vehicles by Finite Element Method

The demand of fossil fuel vehicles has decreased due to carbon emissions. Recently, electric vehicles (EV) with electric motor propulsion have gotten attention due to their zero carbon emissions and high efficiency. In this study, an outer rotor in wheel switched reluctance motor (IWSRM) with 18 poles on the stator and 24 poles on the rotor, designed for the propulsion of electric vehicles, is investigated in two-dimensional Finite Element Method (FEM). The magnetic field distributions of IWSRM for different rotor positions at nominal current are obtained. Then, the torque and phase inductance are calculated. As a result, the designed IWRSM provided low torque.

Analysis of AC Loss in High-Speed Switched Reluctance Motor for Electric Vehicle Considering Winding Axial Transposition

The 3-D finite element method (FEM) has been widely used for accurate analysis of winding loss with winding axial transposition angle considered. However, its application is limited due to long computation time and complex modeling processes. To address these problems, this article proposed a 2-D equivalent permeability modeling method (EMM). First, according to the proposed method, the 3-D winding model with axial transposition angle could be equivalent to several segmented 2-D models. Through equivalent axial length coefficients, 2-D models with different axial lengths could be solved in one project. Using appropriate segment and equivalent coefficients, to a great extent, the inherent error of the 2-D model could be reduced. Second, with equivalent permeability and conductivity, current density distribution and winding ac loss could be calculated. To verify the correctness and robustness of the proposed method, the study was conducted in the five-parallel-strand model. Single-tooth models with concentrated windings were built to verify the evaluated winding loss. In addition, a 20-kW 12/8 high-speed switched reluctance motor was manufactured, and the temperature rise was tested to verify the effect of winding loss on the temperature rise. Through the comparison of experiments and FEM, the EMM is verified to be with high accuracy and computational efficiency to analyze the ac loss and current distribution.

Model Free Adaptive Control of Switched Reluctance Motor for Electric Vehicle

In this paper, the model free adaptive control method of switched reluctance motor for electric vehicle is studied. Based on the torque distribution control of SRM, a SRM control strategy based on torque current hybrid model based on RBF neural network is proposed in this paper. Based on the deviation between the dynamic average value and instantaneous value of SRM output torque, the online learning of RBF neural network is realized. At the same time, this paper constructs a torque current hybrid model, obtains the current variation law of SRM under low torque ripple operation, and reduces the torque ripple of SRM. The SRM torque distribution control is realized on the SRM experimental platform. Compared with the voltage chopper control method, the experimental results show that the torque ripple of SRM can be reduced by adopting the torque distribution control strategy.

Intelligent Speed Regulation Control of Switched Reluctance Motor of Electric Vehicle Based on Neural Network Parameter Identification

Based on the analysis of the related theories of switched reluctance motor, this paper designs and implements the intelligent speed regulation system of switched reluctance motor for electric vehicle. The speed regulation system has the characteristics of high efficiency and energy saving, wide speed regulation range and small starting current. The system also has the advantages of large starting torque, frequent start and stop, forward and reverse switching, high torque / inertia ratio and four quadrant operation. The system can provide a good solution for variable speed drive. The digital controller of the system is composed of TMS320F2812 DSP and EPM7128S CPLD, which can realize the starting, electric and braking functions of electric vehicles. Experiments show that the switched reluctance motor drive system for electric vehicle has good control performance and strong fault tolerance. The system can meet the requirements of various working conditions of electric vehicles and has broad development prospects.

Design of Outer-Rotor Permanent-Magnet-Assisted Synchronous Reluctance Motor for Electric Vehicles

Today’s automotive industry has focused its studies on electric vehicles (EVs) or hybrid electric vehicles (HEVs) rather than gasoline-powered vehicles. For this reason, more investment has been made in electric motors with high efficiency, high torque density, and high-power factor to be used in both EVs and HEVs. In this study, an outer-rotor permanent-magnet-assisted synchronous reluctance motor (PMaSynRM) with a new rotor topology was designed for use in an EV. The design has a transversally laminated anisotropic (TLA) rotor structure. In addition, neodymium-iron-boron (NdFeB) magnets were used in rotor topology. The stator slots were designed as distributed windings, so torque ripples are minimized. At the same time, the maximum electromagnetic torque was achieved. The analysis of the designed motor was carried out using the finite element method (FEM). Optimal values of motor parameters were obtained by improving the rotor geometry of the three-phase PMaSynRM in order to obtain maximum torque and minimum torque ripple in the design. The motor is in a 48/8 slot/pole combination, a speed of 750 rpm and a power of 1 kW. The simulation results showed that the design achieved maximum torque and minimum torque ripple.

Analysis on the design and temperature field of switched reluctance motor for electric vehicle

Specific to the wide speed range and large instantaneous power of the motor for electric auto-mobile, a 110kW auto-mobile switched reluctance motor is designed. The electromagnetic torque, induce voltage are calculated and the electromagnetic performance is met the requirement of electric vehicle power. The copper loss and core loss are obtained based on finite element model. In addition, the coefficient of thermal conductivity is obtained based on physical properties of materials. At last, the 3-D temperature field model is established based on ANSYS workbench and the distribution of temperature is calculated. The results show that the motor winding temperature is running smoothly under water-cooling condition. The rotor temperature is maximum, the temperature of stator winding is slightly higher than the temperature of stator core, which conforms to the thermal design requirement of motor and lays certain foundation for the optimized analysis of such kind of motor.

Optimal Design of PMa-SynRM for Electric Vehicles Exploiting Adaptive-Sampling Kriging Algorithm

Motor design can be said as multi-modal optimization problem, as many performances should be considered. In addition, a time-consuming finite element method (FEM) is required for accurate analysis of the motor, and such computational burden becomes worse when the FEM is applied to multi-modal optimization problem. In this paper, adaptive-sampling kriging algorithm (ASKA) is proposed to relieve the computation cost of multi-modal optimization problem. The ASKA utilizes kriging interpolation model with generated samples by Compact Search Sampling (CSS) and Exclusive Space-filling Method (ESM). The CSS improves the accuracy of the solutions by generating samples near the expected solutions, and the ESM guarantees the diversity of solutions by generating samples far from existing samples, avoiding solution-near area. Using CSS and ESM, the ASKA adjusts the number of samples effectively and reduces function call considerably. The superior performance of the ASKA was verified by mathematical test functions with complex objective function regions. To validate the feasibility of actual electric machines, the ASKA was applied to optimal design of permanent magnet assisted synchronous reluctance motors for electric vehicles and optimum design with diminished torque ripple is derived.

Iron loss and temperature analysis of switched reluctance motor for electric vehicles

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.

Predictive Direct Torque Control of Switched Reluctance Motor for Electric Vehicles Drives

The electrical drive systems utilized in Electric Vehicles (EVs) applications must be reliable and high performance. To providing these specifications, it is essential to design high-efficiency electric motors and develop high-performance controllers. This study introduces direct torque control of Switched Reluctance Motor (SRM) for electric vehicle applications using Model Predictive Control (MPC) technique. The direct torque control using MPC is proposed to maintain the motor torque and motor speed to tracking desired signals with a satisfactory response. In this study, the MPC algorithm was programmed in C- language, and the simulation tests were performed using a non-linear model of 6/4 - 60 kW SRM that is fed with the symmetrical converter. The proposed controller was tested under different load conditions to verify the robustness of the controller, as well as at variable speeds to investigate the tracking performance. Thanks to the proposed method, the SRM torque ripples, stator copper losses, and average switching frequency of the power converter can reduce effectively due to applying a cost function that combines multiple objectives. The obtained outcomes show the effectiveness of the suggested approach compared to conventional direct torque control techniques.

Adopting the Topology Optimization in the Design of High-Speed Synchronous Reluctance Motors for Electric Vehicles

This article deals with the design of high-speed synchronous reluctance motors for electric vehicle applications. The need to enhance the power density and to lower the cost leads to research on high-speed motors with a reduced amount of rare earth. Pure synchronous reluctance motors potentially operate at high speed and exhibit a cost-effective rotor compared to permanent magnets and induction motors. Nevertheless, they present reduced performances in deep flux weakening operations, in particular when the so-called radial ribs are introduced to increase the mechanical robustness of the rotor. In this article, the introduction of the radial ribs and the related design challenges are investigated and discussed. The adoption of the topology optimization tool that is able to optimize the amount, the positioning, and the sizing of suitable structural ribs is presented. A design flow integrating the topology optimization is presented. The approach leads to an original positioning of the radial ribs able to preserve the performance of the motor at high operating speed enhancing the mechanical integrity of the rotor.

Design and optimisation of an In‐wheel switched reluctance motor for electric vehicles

To improve the mechanical performance of the In-wheel switched reluctance motor (SRM) used in electric vehicles (EVs), structure design and geometrical multi-objective optimisation strategy for the In-wheel SRM were developed in this study. The design method for major parameters of the In-wheel SRM was presented by means of design specifications of the EVs. According to requirements of the EVs, four indicators of the SRM were defined to evaluate the development of the SRM and perform the optimisation. To simultaneously improve the static performance of the SRM, a novel multi-objective simultaneous optimisation function was proposed by using four weighted factors and considering sensitivity analysis of the design variables on indicators. A four-phase 16/20 In-wheel SRM with an outer rotor was designed and optimised based on the proposed multi-objective optimisation method. The influence of design variables on average torque, torque ripple, efficiency, and torque density was analysed based on a combination of finite element analysis and orthogonal experiment design method. The static and dynamic torque performances of the optimised SRM were evaluated and compared with those of the initial motor. The comparison results showed that the proposed multi-objective simultaneous optimisation strategy can greatly improve the static and dynamic torque performances of the SRM.

A Direct Instantaneous Torque Control of Switched Reluctance Motor for Electric Vehicles based on FWA-LSSVM Improved ADRC

Electric vehicles are considered as a new generation of transport to solve the energy crisis, switched reluctance motor (SRM) has been widely used in electric vehicle drive system. Indirect instantaneous torque control (DITC) for SRM, Traditional PI regulator has some defects, A new direct instantaneous torque control for SRM based on active-disturbance rejection control (ADRC) optimized by least squares support vector machines (LSSVM) method is proposed in this paper, using the Firework Algorithm (FWA) to optimize the penalty factor and kernel parameters of the LSSVM model to obtain the optimal FWA-LSSVM regression model, Finally, the ADRC controller embedded the FWA-LSSVM optimal regression model is analyzed and optimized to improve the dynamic response speed and anti-jamming capability of the system and enhance the robustness of the system. MATLAB simulation results show that the feasibility and superiority of the method.

Multi‐objective optimisation design of two‐phase excitation switched reluctance motor for electric vehicles

Compared with the single-phase excitation mode of the switched reluctance motor (SRM), the statictorque curves of the SRM with two-phase excitation mode are more flexuous andwide flat regions are absent from the curves. To improve the static torqueperformance of the SRM with two-phase mode, geometrical multi-objectiveoptimisation strategy is developed in this paper. Considering the requirementsof the electric vehicles, four indicators are presented and defined to evaluatethe development of the SRM. Six main independent variables are determined and anovel multi-objective optimisation function was proposed to simultaneouslyimprove static performance of the SRM. Furthermore, to simplify theoptimisation, a sensitivity index that reflects the relative importance of eachvariable is developed to eliminate insignificant variables. The four-phase 8/6SRM with two-phase mode is optimised by means of the proposed multi-objectiveoptimisation method based on effects and sensitivity analysis of the designvariables on indicators. The static and dynamic torque performance of theoptimised SRM is evaluated and compared with those of the initial motor. Thecomparison results show that the multi-objective simultaneous optimisationstrategy can improve the static average torque, static average torque per mass,and global index by 18.09, 12.08, and 6.57%,respectively.