Switched Reluctance Motor Research Articles

Optimizing Torque Ripples In Switched Reluctance Motor Via ANN

Optimizing Torque Ripples In Switched Reluctance Motor Via ANN

Fuzzy controlled modified reduced switch converter for switched reluctance motor under dynamic loading

In this paper, modified reduced switch converter topology is used to drive 8/6 pole, 7500 W switched reluctance motor (SRM) with an electric vehicle (EV) load. Fuzzy logic control (FLC) is developed for the modified converter topology and its performance is compared with the proportional integral (PI) controller. Analytical equations, switching pulses and different mode of operation are presented for modified reduced switch converter using double phase magnetization scheme. The converter topology adopts a modified switching sequence i.e., magnetization then freewheeling before demagnetization. It offers lesser torque ripples, reduced phase current and need only four switches for a 4-phase SRM drive. Modified reduced switch converter is simulated in MATLAB-simulation to investigate and compare the steady state waveforms and transient speed response of the PI and FLC. Torque ripple in modified converter is 50% less than the classical converter. Peak overshoot and settling time performance of FLC is superior as compared to PI, when applied to modified converter with EV loading.

An Improved Model-Predictive Torque Control of Switched Reluctance Motor Based on Sector Adaptive Allocation Technology

An Improved Model-Predictive Torque Control of Switched Reluctance Motor Based on Sector Adaptive Allocation Technology

An Improved Control Strategy to Reduce Torque Spikes and Ripple for Bearingless Switched Reluctance Motors

An Improved Control Strategy to Reduce Torque Spikes and Ripple for Bearingless Switched Reluctance Motors

Parameter Identification of Nonlinear Flux-Linkage Model for Switched Reluctance Motor Based on Chaotic Diagonal Recurrent Neural Network

Parameter Identification of Nonlinear Flux-Linkage Model for Switched Reluctance Motor Based on Chaotic Diagonal Recurrent Neural Network

Direct Control Method for Linear-Rotary Switched Reluctance Motor With Two Radial Windings

For Linear-Rotary Switched Reluctance Motors (LRSRMs) with two radial windings, the coupling between torque and axial force increases the complexity of control. Due to the calculation of current in existing control method for LRSRMs, the complicated derivation of current expression was necessary, and some constraints were also introduced which meant the difficulties on designing the current control algorithm were greatly increased. In order to solve these problems, a direct torque and direct axial force (DTC&DAFC) control method is proposed in this paper. By the way of selecting appropriate space voltage vectors, the proposed method can directly regulate torque and axial force at the same time to achieve rotation and linear motion and significantly reduce the ripple of the torque. Moreover, the mechanism of two-DOF motion and the principle of the proposed method are demonstrated in detail based on a 6/4 LRSRM with two radial windings. Based on MATLAB/Simulink and the experimental prototype, the feasibility of the proposed control method has been verified according to the simulation and experimental results.

Review Design and Simulation of a Switched Reluctance Motor Using Sensorless Control System

Abstract: This paper mainly introduces the acquisition of the position information of the switched reluctance motor through the inductance, which can make the switched reluctance motor(SRM) correct commutation. The main method is to apply highfrequency and low-duty pulse voltages to the two non-conducting phases of the switched reluctance motor when the motor is in low-speed operation, so that the non-conducting phase generates a response current through the rising slope of the response current The current change rate is obtained by the difference with the falling slope, and then the current change rate is converted into inductance through a formula, and whether the inductance reaches the inductance threshold is judged whether it reaches the commutation position, and the motor is subjected to timely and accurate commutation processing. This method is realized by matlab/simulink simulation, and combined with the high-speed inductance method obtained by the flux ratio current, to realize the position sensorless technology combined with the inductance method in the full speed cycle, and the simulation verifies that the low-speed and high-speed algorithms can be smooth Switch, and can realize its commutation control function, and It provides simulation support for applications such as lawn mower.

A Lambert importance model‐based reliability design method for power converters in switched reluctance motor systems

SummaryThe reliability of power converters is crucial for achieving high‐performance operation in switched reluctance motor (SRM) systems. However, there is a notable deficiency in reliability‐oriented design of power converters that can effectively integrate both static and dynamic reliability indicators. To address this issue, this paper proposes a reliability design methodology for power converters based on the Lambert importance model, aimed at enhancing reliability of SRM systems. Firstly, the modeling principles of Lambert importance model are presented. Subsequently, a reliability design method is proposed to maximize reliability within a unit economic cost framework. Especially, the proposed design scheme is designed to maximize reliability enhancement potential through a two‐pronged approach: strategic topology selection informed by potential reliability assessments and component selection guided by importance calculations. Meanwhile, dynamic reliability evaluation is carried out to form a double‐loop reliability feedback and increase the credibility of design scheme. Finally, an example is developed to verify the validity of proposed reliability design scheme.

Monitoring of Stator Winding Insulation Degradation through Estimation of Stator Winding Temperature and Leakage Current

Switched Reluctance Motors (SRMs), Permanent Magnet Synchronous Motors (PMSMs), and induction motors may experience failures due to insulation-related breakdowns. The SRM rotor is of a non-salient nature and made of solid steel material. There are no windings on the rotor. However, the stator is composed of windings that are intricately insulated from each other using materials such as enamel wire, polymer films, mica tapes, epoxy resin, varnishes, or insulating tapes. The dielectric strength of the insulation may fail over time due to several environmental factors and processes. Dielectric breakdown of the winding insulation can be caused by rapid switching of the winding current, the presence of contaminants, and thermal aging. For reliable and efficient operation of the SRMs and other electrical machines, it is necessary to take into account the physics of the winding insulation and perform appropriate diagnostics and estimations that can monitor the integrity of the insulation. This article presents the estimation problem using a Genetic Algorithm (GA)-optimized Random Forest Regressor. Empirical properties and measurable quantities in the historical data are utilized to derive temperature and leakage current estimation. The developed model is then combined with a moving average function to increase the accuracy of prediction of the stator winding temperature and leakage current. The performance of the model is compared with that of the Feedforward Neural Network and Long Short-Term Memory over the same winding temperature and leakage current historical data. The performance metrics are based on computation of the Mean Square Error and Mean Absolute Error.

Design, FEM analysis and development of switched reluctance motor electric drive for TRI-wheeler E-vehicle application

Electric vehicles have seen substantial growth in recent years in the emerging economies of the world. The current market scenario of E-vehicles is dominated by PMSM or BLDC motors due to their higher torque-to-power density, and efficiency with added performance metrics of the motor. However, the higher capital cost of permanent magnets makes the motor designers to consider an alternative to magnetic motors, the so-called Switched Reluctance Motors (SRM). With proper FEM analysis and controller design, if SRMs can able to achieve the performance metrics of a PMSM/BLDC, it will be a breakthrough in the automotive sector with affordable prices. Based on the aforementioned facts, this research work focuses on SRM as a viable alternative to the existing PMSM/BLDC motor. The work concentrates on the design and development of an 8/6 SRM for a Tri-wheeler E-vehicle application. The designed motor is fabricated, tested and controlled by WAVECT, an FPGA-based real-time digital controller which is used to control the commutation of the 8/6 SRM. The yielded response satisfactorily proves that the designed 8/6 SRM can be effectively used for the Tri-wheeler E-vehicle application, thereby paving the way for sustainable energy conservation in the automotive sector.

Control and Analysis of a Hybrid-Rotor Bearingless Switched Reluctance Motor with One-Phase Full-Period Suspension

In the traditional control scheme of a 12/8-pole bearingless switched reluctance motor (BSRM), radial force and torque are usually controlled as a compromise due to the conflict between their effective output areas. Additionally, each phase requires individual power circuits and is excited in turn to produce a continuous levitation force, resulting in high power device requirements and high controller costs. This paper discusses a 12/8-pole single-winding hybrid-rotor bearingless switched reluctance motor (HBSRM) with a hybrid rotor consisting of cylindrical and salient-pole lamination segments. The asymmetric rotor of the HBSRM slightly increases the complexity of its structure and magnetic circuit, but makes it possible to generate the desired radial force at any rotor angular position. A control scheme for the HBSRM is developed to utilize the independent excitation of the four windings in one phase to generate the desired levitation force at any rotor angular position, and it requires only half the number of power circuits used in the conventional control scheme of a 12/8-pole single-winding BSRM. Different from the average torque chosen to be controlled in traditional methods, this scheme directly regulates the instantaneous total torque produced by all excited phases together and presents a current algorithm to optimize the torque contribution of each phase so as to reduce torque pulsation, and the improved performance of this bearingless motor is finally validated by simulation analysis.

Comparative assessment of a novel 8/18 multi-teeth with conventional 8/10 in-wheel SRM for an E-Scooter

Electric scooters are increasingly gaining popularity in India owing to rising global crude oil prices and rising levels of vehicular pollution. Most of them are currently powered by expensive in-wheel (IW) permanent magnet (PM) brushless DC motors. Owing to their simplicity, and ruggedness while being cost-effective (since they do not employ PMs), switched reluctance motors (SRMs) are a viable alternative. Despite these benefits, SRMs possess drawbacks such as low torque density and inferior efficiency. Recently, a multi-teeth (MT) SRM with an improved performance was reported. However, the design of MTSRM topologies and their electromagnetic performance have not been explored sufficiently. In this paper, a design formula governing the selection of the number of MT and rotor poles for MTSRMs has been proposed. Using this, a novel four-phase 8/18 IW-MTSRM is derived and proposed for an E-scooter. The characteristics of the proposed SRM are numerically compared with a conventional 8/10 SRM based on magnetic characteristics, efficiencies and steady-state operation for the complete torque-speed range. Results indicate that the proposed 8/18 MTSRM has a higher peak torque capacity, torque density, superior drive cycle efficiency and reduced torque ripple. Further, the FEA model is validated experimentally on a downsized 8/18 MTSRM prototype.

Switched reluctance motor core loss estimation with a new method based on static finite elements

Switched reluctance motor core loss estimation with a new method based on static finite elements

Design and Fabrication of Switched Reluctance Motor for Energy Efficient Operation by Minimizing Torque Ripple

Around the world, motor is consuming more than 40% of the total-generated electrical energy. Accordingly, energy efficient electrical drives are the needs of the hour. The Switched Reluctance Motor (SRM) is more energy efficient than other kinds. Since SRM has a rugged structure, it has inherent fault tolerance characteristics and is cost-effective than synchronous and induction machines. Nevertheless, the application of such a motor is limited due to low torque density, torque ripples and power losses because of control circuit. In this research work, the author proposed a novel-designed SRM, which is achieved by optimizing stator and rotor pole arc. Alongside, a novel control circuit, which has single transistor, is proposed. The modification of stator and rotor pole arcs assists in the reduction of the torque ripple. The stator pole arc is modified from 32 degree to 36 degree, and the rotor pole arc is modified from 30 degree to 28 degree. Thus, the torque ripple is reduced from 3.25 to 2.92 Nm, and thus, the useful torque is increased from 4.94 to 5.2 Nm. Furthermore, a single transistor switching device is used instead of the conventional one with four switches. Hence, energy loss on the control circuit is significantly reduced. From the experimental analysis, it is found that, with-pole-arc modified SRM has higher efficiency than the one without it.

Evaluation of Electric Vehicle Performance Characteristics for Adaptive Supervisory Self-Learning-Based SR Motor Energy Management Controller under Real-Time Driving Conditions

The performance of an electric vehicle (EV) notably depends on an energy management controller. This study developed several energy management controllers (EMCs) to optimize the efficiency of EVs in real-time driving conditions. Also, this study employed an innovative methodology to create EMCs, efficiency maps, and real-time driving cycles under actual driving conditions. The various EMCs such as PID, intelligent, hybrid, and supervisory controllers are designed using MATLAB/Simulink and examined under real-time conditions. In this instance, a mathematical model of an EV with a switched reluctance (SR) motor is developed to optimize energy consumption using different energy management controllers. Further, an inventive experimental approach is employed to generate efficiency maps for the SR motor and above-mentioned controllers. Then, the generated efficiency maps are integrated into a model-in-loop (MIL)-based EV test platform to analyze the performance under real-time conditions. Additionally, to verify EV model, a real-time driving cycle (DC) has been developed, encompassing various road conditions such as highway, urban, and rural. Subsequently, the developed models are included into an MIL-based EV test platform to optimize the performance of the electric motor and battery consumption in real-time conditions. The results indicate that the proposed supervisory controller (59.1%) has a lower EOT SOC drop compared to the PID (3.6%), intelligent (21.5%), and hybrid (44.9%) controllers. Also, the suggested controller achieves minimal energy consumption (44.67 Wh/km) and enhances energy recovery (−58.28 Wh) under different real-time conditions. Therefore, it will enhance the driving range and battery discharge characteristics of EVs across various real-time driving conditions.

A C-Core Connected Two-Phase Switched Reluctance Motor With Embedded Permanent Magnets for Developed Torque Enhancement

Conventional switched reluctance motors (SRMs) face challenges like low torque density and high noise. To overcome these challenges, the structure of SRMs can be modified. This paper introduces a new hybrid-excited 16/18 two-phase SRM with a C-core structure. Each pole of the C-core has two teeth, which develop a positive torque during the rotor rotation; this enhances the torque and torque density of the motor. To show the merits of the proposed SRM with PMs, its static and dynamic characteristics, including flux density, flux-linkage, and torque, are obtained and compared with the SRM with no PMs, the 8/12 two-phase conventional SRM, and other motors with the same volume; a significant match was achieved. Finally, both proposed SRMs were prototyped and tested. Comparing the simulation and test results elucidates that the proposed SRM with PMs has unique high output power, torque, and efficiency.

A simple approach for the computation of magnetic characteristics of 4-phase switched reluctance motor

Switched reluctance motor (SRM) is non-linear in nature due to non-uniform air gap between stator and rotor that is produced from doubly salient poles. To control the operation of non-linear motor, a precise modelling of magnetic characteristic is essential. Traditionally magnetic equivalent circuit, finite element method (FEM) and experimental approaches have been used to derive magnetic characteristics of SRM. These methods involve complex computational steps and numerous assumptions for its calculations. To avoid this complexity, a simple approach is suggested in this paper to compute magnetic characteristics of 4-phase SRM. In this approach, SRM phase inductance is measured directly to identify the location of rotor with respect to stator from unaligned to aligned position. Then, single phase of SRM is excited through asymmetric converter and voltage and currents of corresponding phase is recorded with rotor being blocked using indexing head. Later recorded values are used to compute the magnetic characteristics from unaligned to aligned position. The proposed method is carried out using field programmable gate array (FPGA) controlled 8/6, 4-phase SRM. Further, accuracy of obtained magnetic characteristic is verified using FEM. In addition, fidelity of the magnetic characteristic is also validated by developing a dynamic model of SRM in MATLAB/Simulink

Modified switching control of SRM drives for electric vehicles application with torque ripple reduction

The switched reluctance motor (SRM) offers extensive prospects, particularly within the realm of electric vehicles (EVs). Its robust construction, wide speed range, high torque density, and efficiency provide significant advantages that surpass other motors. Nonetheless, controlling these motors is more intricate when compared to conventional DC brushed or AC motors. This complexity arises due to the non-linear inductance characteristics of SRMs, resulting in undesirable effects like torque ripple, vibrations, and noise. Using the conventional full-bridge inverter, three switching approaches are highlighted for various operating modes of an EV. This aims to reduce costs and the number of switching pulses, leading to a more compact system, elimination of dead time, and switching losses. The MATLAB/Simulink platform was utilized to examine the operational effectiveness of a three-phase 6/4 poles SRM drive. Additionally, this paper focuses on mitigating torque ripple concerns by employing an adaptive neuro-fuzzy inference system (ANFIS) controller that has better efficiency and superior responses compared to conventional controllers such as fuzzy logic control (FLC) and proportional integral (PI) control. The results of the simulation encourage the practical implementation of the system, which is the next step in the author’s research.

Performance Analysis of a Novel Axial Radial Flux Segmental Rotor Switched Reluctance Motor

Based on the characteristics of axial flux switched reluctance motor (SRM) and radial flux SRM, this paper proposes a new type of axial radial flux segmental rotor switched reluctance motor (ARFSRSRM). The motor has the left and right dual axial stator structures, which forms a kind of axial flux path with the segmental rotor in the middle, and a radial stator structure, which shares a kind of radial flux path with the segmental rotor on the outside of the motor. Compared with the conventional SRM, this motor combines the advantages of high output torque and torque density due to the inclusion of two kinds of flux paths, making it suitable for high-efficiency and high-torque fields such as electric vehicles. In this paper, the topology and operating principle of the new motor are first introduced. Then the initial structural parameters are derived, and the multi-objective optimization of the proposed motor is carried out using Taguchi’s algorithm. The static and dynamic performance of the motor is comprehensively analyzed using the 3-D finite element method. Finally, the experimental results obtained through the trial production of a prototype machine verify the good performance of the new motor.

A comprehensive review of different electric motors for electric vehicles application

Electric vehicles (EVs) offer several advantages over internal combustion engines (ICE), including high energy efficiency, noise reduction, low maintenance, and a wider speed range. This results in lower fuel consumption, reducing dependency on oil imports and enhancing energy security. The motor drive is a critical component of EVs, providing the necessary propulsion force. This paper presents a comprehensive comparison of state-of-the-art motors suitable for EV applications, including DC motors, induction motors (IM), brushless DC motors (BLDC), permanent magnet synchronous motors (PMSM), and switched reluctance motors (SRM). Various design aspects relevant to traction applications, such as cost, reliability, efficiency, torque, fault-tolerance ability, excitation arrangements, and power density are also addressed. The performance of an EV based on the SRM drive is analyzed using MATLAB Simulink, with a special focus on parameters like speed, torque, flux, and state of charge (SOC). The review highlights that SRM drives have significant potential in EVs due to their reliable structure, fault tolerance capability, and magnet-free design. However, their application in EVs is currently limited due to torque ripples, as evident from the simulations. This paper is expected to serve as a foundation for further enhancing the performance of SRM drives for EV applications.