Flux-switching Motor Research Articles

Analysis and Comparison Between Flux-Switching Motors With Pole-Changing and Hybrid-Excited Designs

Analysis and Comparison Between Flux-Switching Motors With Pole-Changing and Hybrid-Excited Designs

Design study on hybrid excitation flux switching motor for electric taxiing system in aircraft

Design study on hybrid excitation flux switching motor for electric taxiing system in aircraft

Sürekli mıknatıslı akı anahtarlamalı motorda mıknatıs, stator ve rotor geometrilerinin tork ve tork dalgalanmasına etkisinin incelenmesi

Bu çalışmada, referans alınan bir sürekli mıknatıslı akı anahtarlamalı motora (SMAAM) ait mıknatıs geometrisi ve konumu ile stator ve rotor çıkıntılarında değişiklikler yapılarak yeni tasarımlar gerçekleştirilmiştir. Referans tasarım olarak daha önce literatüre sunulmuş olan üç fazlı bir SMAAM temel alınmış ve tüm motor yapılarına ait benzetim çalışmaları yapılmıştır. Adil bir kıyaslama yapılabilmesi için benzetim çalışmalarında tüm SMAAM tasarımlarında temel parametre ve kullanılan malzemeler korunmuştur. Yapılan tasarımsal değişiklikler ile kabul edilebilir tork değeri beraberinde düşük tork dalgalanması, üretim kolaylığı ve geniş hız aralığında çalışma yeterliliği elde edilmeye çalışılmıştır. Analiz çalışmaları, elektrik makinalarının analizinde yaygın bir şekilde kullanılmakta olan ve oldukça doğru sonuçlar verebilen sonlu elemanlar yöntemi (SEY) temel alınarak gerçekleştirilmiştir. Referans alınmış olan ve tasarlanan yeni SMAAM yapılarına ait elde edilen sonuçlar kapsamlı bir şekilde karşılaştırılmıştır. Bu karşılaştırmlar da tork değerinde kabul edilebilir azalmalar görülürken tork dalgalanma değerinde ciddi azalmalar olduğu sonucuna varılmıştır.

Performance Enhancement of Flux Switching Motor for Electric Vehicle Applications: An Overview

As the reduction of greenhouse gas emissions becomes crucial, electric vehicles (EVs) are expected to enter the market extensively in the coming years. The efficiency of the electrical motor used in EVs plays a significant role in their overall performance. This paper explores the flux switching motor (FSM) and its applications in EVs. The FSM is compared to other electrical motors, highlighting its potential as a suitable choice for EV traction. Various configurations and techniques are reviewed to enhance the performance of FSMs, including magnetic materials, torque ripple alleviation, and magnetic flux weakening. The advantages and disadvantages of these methods are discussed, providing valuable insights for designing FSMs for EVs. Generally, EV traction requires high torque density and high power density electrical motor. To achieve these goals, high electric and magnetic loading must be considered in design stage of the motor. Application of the FSM may be one of the appropriate option. For many reasons, three-phase FSM is preferred. Considering the base speed of machine in the EV and high electric loading, the FSM with 12 stator teeth and 10 rotor teeth may be the most appropriate choice in which the stator core is oriented and rotor core is nonoriented iron. To enhance the torque density and applied flux weakening method, combination of Nd and Al–Ni–Co magnets is preferred.

Sizing, Modeling, and Performance Comparison of Squirrel-Cage Induction and Wound-Field Flux Switching Motors

In this study, the analytical design and electromagnetic performance comparison of a squirrel-cage induction motor (SCIM) and a wound-field flux switching motor (WFFSM) for high-speed brushless industrial motor drives is undertaken for the first time. The study uses analytical sizing techniques and finite element analysis (FEA) to model and predict the performance of both motors at a 7.5 kW output power. This study includes detailed equations and algorithms for sizing and modeling of both types of motors, as well as performance calculations that aid in motor selection, design optimization, and system integration. The main findings show that the SCIM has superior torque performance for starting and overload conditions, while the WFFSM offers advantages in power factor, efficiency over a wide operating range, and potential for higher peak power output. To this end, the WFFSM is capable of high-speed and high-efficiency operation while the SCIM is suitable for applications requiring variable speed operation. The validation study shows good agreement between analytical and FEA calculations for both motors. The results provide insights into the design and performance characteristics of both motors, enabling researchers to explore innovative approaches for improving their efficiency, reliability, and overall performance.

A Comprehensive Review of Indian Market Scenario and Motor used in Electric Vehicle

Abstract: This paper focuses on better understanding the Indian Electric Vehicle (EV) market scenario based on battery and motor specifications. Electric two-wheelers, three-wheelers, and fourwheelers have different challenges and requirements at the efficient design level. This paper also provides a comprehensive review of brushed DC motors, brushless DC (BLDC) motors, permanent magnet synchronous motors (PMSM), induction motors (IM), switched reluctance motors (SRM), and flux switching motors (FSM) for EV application. Background: The market for EVs is growing rapidly in India as a developing country, and users are looking forward to highly efficient and cost-effective EVs due to the pollution and unavailability of petroleum. Objective: The main objective of this paper is to provide the right choice of EV motor based on vehicle type, driving cycle, and user requirement. Method: This paper comprehensively reviews DC and AC motor drive systems for EV application. Conclusion: Nowadays, manufacturing is mainly inclined towards the BLDC, PMSM, and IM. In contrast, SRM and FSM are in the early stage of development and are mainly used by the researcher. A brushed DC motor is not too famous due to its high running cost, frequent maintenance requirements, and comparatively bulky size.

Review of Control Topologies for Flux Switching Motor

Flux switching Motor (FSM) was invented in the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$19^{th}$ </tex-math></inline-formula> century but started gaining importance after 2000. The simple structure and moderate cost of FSM, in comparison with existing commutated Direct Current (DC) and Permanent Magnet Brushless Direct Current (PMBLDC) motors, have made it attractive for contemporary applications. Currently, FSM is employed in research applications like automobiles, domestic appliances, power generation, etc. To make FSM a viable candidate for these applications, modifications are made to the design, power converters, and control systems of FSM. This article comprehensively reviews the various control topologies adopted for FSM, which encompasses the control of torque and speed. Different control algorithms like 1) linear controllers, 2) sensorless techniques, 3) predictive controllers, and 4) optimization techniques are discussed extensively based on existing literature. Further, a case study is carried out using these control algorithms, and the simulation results are analyzed.

High efficiency flux switching motor

Flux switching motor (FSM) with field excitation is permanent magnet free and attractive for many industrial and domestic applications. However, design with the conventional trapezoidal stator slot has low efficiency and always been a challenge in the state of the art. Further, the finite element analysis (FEA) method for the electromagnetic performance investigation is a powerful tool, but, it has high computational time, computational complexity and drive storage. To address the concern of low efficiency, in this paper, a new single phase 8slots–6poles electrically excited (EE) FSM design with the rectangular stator slot (RSS), salient rotor and non-overlapped windings for pedestal fan applications is been proposed. The proposed RSS EEFSM design is analyzed analytically and the analytical results are validated by FEA method. Finally, experimental test of the proposed EEFSM prototype is performed. The measured results are in a good agreement with the calculated results. Moreover, the proposed RSS EEFSM has higher efficiency as compared to the conventional design.

A New Fault-Tolerant Rotor Permanent Magnet Flux-Switching Motor

This article proposes a new fault-tolerant rotor permanent magnet flux-switching (FT-RPMFS) motor. The key of the proposed FT-RPMFS (PFT-RPMFS) motor is its new rotor topology with the unique configuration of the auxiliary PM (APM), located in the rotor to enhance the air-gap flux density. Besides, the PFT-RPMFS motor incorporates a union rotor structure, which makes it easy to be manufactured and strengthens its mechanical robustness when compared to the conventional FT-RPMFS (CFT-RPMFS) motor with a segregated rotor part, and therefore, the CFT-RPMFS motor is used as a benchmark to prove the performance of the PFT-RPMFS motor. For fair analysis and comparison, all the design parameter dimensions and materials are the same in both the CFT-RPMFS and the PFT-RPMFS motors with the same slot-pole synergy of 20-slot/11-pole. Furthermore, a multi-objective optimization technique is adopted to improve the output torque and reduce the torque ripple. Moreover, since the FT-RPMFS motor is evolved from a stator permanent magnet flux-switching (SPMFS) motor, the SPMFS motor is also selected as another benchmark to verify the superiority of the PFT-RPMFS motor. Finally, a prototype is manufactured and tested to verify the correctness of the theoretical analysis.

Torque Ripples Reduction and Performance Analysis of Electrically Excited Flux Switching Motor

Torque ripples cause acoustic noise, fluctuation in speed, vibration, and reduce lifetime of the motor. The double salient structure of Flux Switching Motor (FSM) has a high air-gap permeance variation that produces high torque ripples. This paper presents an analytical model to reduce air-gap permeance variation and torque ripples of the proposed octane modular stator 8slots-6poles single-phase Electrically Excited (EE) FSM. Furthermore, the rotor pole shaping technique is used to minimize the air-gap permeance variation and therefore, torque ripples of the proposed design are reduced. The electromagnetic performance of EEFSM is analyzed via the Finite Element Analysis (FEA) method. For the proposed design magnetic flux harmonics are reduced by 71&#x0025; and back-EMF harmonics are suppressed by 48.5&#x0025;. Torque ripples of the proposed EEFSM are reduced by 20&#x0025;, cogging torque is diminished by 42.7&#x0025; and average torque is enhanced by 5.8&#x0025;. Finally, the prototype is fabricated and tested experimentally. Calculated values and experimental results are in good agreement and the difference is 3.5&#x0025;-5&#x0025;.

External rotor permanent magnet-less electric motors for traction application: a review

Electric vehicles (EVs) demand variable speed drives with high starting torque, high power density, and appropriate speed-torque characteristics. Due to this, the EV industry widely considers permanent magnet (PM) motors for traction in powertrains. However, the harmful environmental impacts of the PM open the doors to magnet-less machines such as induction motors, synchronous reluctance motors, switched reluctance motors and flux switching motors as alternatives. Direct-drive in-wheel external rotor motors are an appropriate choice in traction applications to mitigate transmission losses. This paper has thoroughly overviewed the magnet-less machines with in-wheel external rotor topology. The discussions are based on magnetic structure variations, winding topologies, parameter optimisation, control algorithms, and mechanical aspects such as thermal and structural aspects involved in these machines. Further, other applications with external rotor motors are also discussed at the end.

48-Volt Energy Efficient Domestic Appliances With Flux Switching Motor Drive System–Design, Simulation, and Comparison

Energy-Efficient domestic appliances are the need of the hour. This paper explores the importance of 48-Volt domestic appliances especially those operated with an electric motor drive system. Sixteen domestic appliances that are having a power range of 12 Watt &#x2013; 1600 Watt are selected. These appliances are usually produced in very large volumes; therefore, one of the most important requirements is efficiency with moderate cost. Commutator motors are widely preferred for those applications in the present commercial market, which lags in efficiency, requires more space and, bulkier. Flux Switching Motor (FSM) is a new variant in brushless direct current (DC) motor, which has a combined advantage of commutator, Switched Reluctance and, Permanent Magnet Brushless DC Motors (PMBLDC). Complete simulation results with the FSM drive system have been carryout and the performance is compared with the commutator DC motor (DCM) and Induction Motors (IM). Simulation results support FSM drive system technology and novel insights follow from this quantitative comparison.

Performance Analysis of a Modular E-Shaped Stator Hybrid Excited Flux Switching Motor With Flux Gaps

This paper proposes a new modular hybrid excited flux switching motor (MHEFSM) with flux gaps, adding the fault-tolerant capability to the proposed motor. The proposed motor uses an E-Shaped stator, as the middle teeth of E-core produce fault-tolerant capability, and in C-core, this capability is eradicated. The no-load flux linkage is calculated by the magnetic network model (MNM) to reduce time and disk storage. The drawback of the constant flux linkage of PM motors is overcome by employing field excitation (FE). The FE helps in regulation flux at higher speeds. The motor leading geometry variables are optimized by using Genetic Global Optimization (GGO). The GGO helped in refining the structure of the motor and has improved the flux linkage by 68.18%, average torque and torque density by 62.35% each, reduced torque ripples by 20.62%, and cogging torque by 18.52%. The volume of permanent magnet (PM) in the proposed MHEFSM is reduced by 36.24%, and 48.49% higher average torque and torque density is obtained compared to the state of art motor proposed in the literature. Furthermore, a 3D analysis of the proposed MHEFSM is done to further evaluate the electromagnetic performance.

Analysis of Influence of Stator and Rotor Pole Shape on Electromagnetic Performance of Flux Switching Motor With Segmental Rotor

According to the relationship between the stator and rotor structure and magnetic flux density of the traditional flux switching motor with segmental rotor (SFSM), the mathematical model of the SFSM was established. It was found that the height of the stator pole shoe has a great influence on the no-load electromagnetic characteristics of the motor. After the flux barrier was added on the segmental rotor, it can effectively solve the problem that the positive and negative half period of the no-load electromotive force (EMF) waveform of the motor with low pole shoe height. Using the method of finite element (FEM) parametric simulation, the optimal size of the flux barrier was obtained. Compared with the traditional SFSM, the even harmonics in the phase winding EMF waveform were greatly reduced, and the inductance waveform tends to be sinusoidal. Finally, a prototype was made, and the correctness of the new segmental rotor structure was verified by experiments.

Design optimization of coreless stator axial flux-switching motor

This study aimed to provide the analytical design, optimization, and three-dimensional (3D) simulation through finite element method of a coreless stator axial field flux-switching motor (AFFSM). The motor consists of two indented rotors with a coreless stator between them consisting of a magnet and winding. First of the motor electrical and magnetic design was performed and its basic parameters were calculated. Then, the optimization of the machine was evaluated implementing the Taguchi algorithm in order to minimize the motor cogging torque. Some of the basic motor dimensions, such as the magnet length and width, the rotor tooth width and height, and the back iron thickness, were selected as optimization variables, and the best combination of these variables was obtained by changing them in a certain range to achieve the desired objective. Then, the accuracy of analytical design and optimization was evaluated through forming a 3D finite element method (FEM) of the motor and investigating its performance. Comparison of the optimized and primary motor revealed that the optimal design had a better performance than the initial. Finally, a prototype of the proposed motor was fabricated and tested, which indicated that the experimental results were largely similar to the analytical results.

Analytical Modeling, Optimization, and Electromagnetic Performance Analysis of Electrically Excited Flux Switching Motor

Flux switching motors (FSMs) with conventional stator slots have a relatively low copper slot filling factor. In this article, a new octane modular stator with pentagon-shaped slot electrically excited FSM (EEFSM) that has a comparatively higher copper slot filling factor is analyzed analytically to reduce computational complexity, high computational time, and high drive storage. The analytical results of the proposed EEFSM are validated via the finite element method. Furthermore, the initial design is optimized to improve the electromagnetic performance, and finally the prototype is fabricated and tested experimentally. There is good agreement among the analytical, finite element analysis (FEA), and experimental results with variations of 3%–5%. The average torque of the optimized design has improved by 30%, cogging torque is suppressed by 36%, and torque ripples have reduced by 38%, which have improved the performance of EEFSM in terms of low acoustic noise, low vibration, and longer motor lifetime. The proposed octane modular stator can be easily unfolded for windings maintenance, coils placement, and motor transportation in case of large-size applications.

Design and Analysis of Dual Mover Multi-Tooth Permanent Magnet Flux Switching Machine for Ropeless Elevator Applications

A dual mover yokeless multi-tooth (DMYMT) permanent magnet flux switching motor (PM-FSM) design is presented in this article for ropeless elevator applications. The excitation sources, including a field winding and permanent magnet, are on the short mover in the proposed design structure, whereas the stator is a simple slotted iron core, thus reducing the vertical transportation system cost. The operational principle of the proposed DMYMT in PM-FSM is introduced. The proposed dual mover yokeless multi-tooth Permanent Magnet Flux Switching Motor is analyzed and compared for various performance parameters in a Finite Element Analysis package. The proposed machine has high thrust force and cost-effectiveness compared to conventional dual permanent magnet motor. Finally, this paper also develops an analytical model for the proposed structure, validated by comparing it with Finite Element Analysis simulation results. Results show good agreement between analytical prediction and Finite Element Analysis results.

Comparative Study on Hybrid Excitation Flux Switching Motors without and with Variably Magnetizable Permanent Magnets for Electrified Vehicle Propulsion

A demand for high efficiency traction motors has been accelerated by the promotion of electrified vehicles, such as battery and fuel cell electric vehicles. As a part of development of the high efficiency traction motor, this paper reports a comparative study on two kinds of hybrid excitation flux switching motors (HEFSM) as a variable flux machine. One is the conventional HEFSM, which consists of a stator with constantly magnetized-permanent magnets, field excitation coils (FECs) and three-phase armature windings, and a rotor with salient poles like a switched reluctance motor. The other is a HEFSM employing variably magnetizable-permanent magnets (VM-PMs) that replace a part in the FEC slot area in the conventional one. Based on the variable magnetization nature of VM-PMs, the latter HEFSM promises that the replacement of magnetomotive force (mmf) of FECs with that of the VM-PMs makes the motor efficiency better at both low- and high-speed under the low-torque condition, that is, at both urban driving or highway cruising. To verify that, finite element analysis- (FEA)-based design simulations, as well as experimental performance evaluations for the two kinds of HEFSM, were conducted under reasonable dimensional and electrical constraints. As a result, it is shown that the latter HEFSM can achieve higher motor efficiency at the low-torque and high-speed region while keeping the motor efficiency at the low-torque and low-speed region.

Investigation On High Temperature Superconducting Linear Flux-Switching Motors With Different Mover and Stator Pole Pitch Ratios For Urban Railway Transit System

Linear Induction Motors (LIMs) are popular as driving motors in urban railway transit systems due to their simple and robust stator structures. However, the efficiency and power factor of LIM are lowered because of its eddy effect. As a promising alternative, Linear Flux Switching Permanent Magnet (LFSPM) motor offers high electromagnetic performance while keeping its stator simple. Despite these merits, the adoption of Permanent Magnets (PMs) of LFSPM motors influences their flux-weakening ability, thus leading to narrow speed range. To solve this problem, it is feasible to use High Temperature Superconducting (HTS) coils to replace PMs, forming HTS Linear Flix Switching Motor (HTS-LFSM). Among various parameters that influence the performance of HTS-LFSM, ratio of primary and secondary pole pitches is a leading parameter. Aim at investigating the relationship between pole pitch ratios and electromagnetic performance, different typical pole pitch ratios are compared against each other based on several common principles. The merits and drawbacks are analyzed with the help of Finite Element Method (FEM), and some conclusions are drawn.

Fault-Tolerant Operation Control Strategy for Combined Winding Bearingless Flux-Switching Permanent Magnet Motor Drive System With One Opened Phase

The failure of the inverter bridge arm or the open circuit of the phase winding may occur during the operation of a combined winding bearingless flux-switching motor, causing both rotor rotation and suspension to malfunction, hence fault-tolerant control is vital for the motor's reliability and stability. In this paper, a fault-tolerant operation control strategy for combined winding bearingless flux-switching permanent magnet motors under open-circuit fault condition is proposed. Firstly, how to control the electromagnetic torque and suspension force acting on the rotor with the combined winding structure is explained, and then the mathematical models of the torque and suspension force which can be controlled individually by different current components are deduced in detail. Afterward, the relation of the phase current without and with winding fault is discussed, and the operation conditions of maintaining constant torque and suspension force after fault are demonstrated. Whereupon, the fault-tolerant control block diagram is constructed. Finally, the experimental results are presented to demonstrate the performance of the proposed strategy.