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The purpose of this paper is to propose a novel hybrid excitation permanent magnet synchronous generator (HEPMSG) utilizing tooth harmonic for excitation, the structural features and operation principle of which are also described.

To obtain the operation performance quickly, this paper derives the mathematical model of the machine system represented by circuit, and analyzes the operation mode of rectifier circuit in the tooth harmonic excitation system, then the standard state equations for each operation mode are obtained. Combining the inductance parameter of this machine with the load resistance and inductance, the armature current waveform, the field current waveform and tooth harmonic winding current waveform are obtained by using the numerical method to solve the standard state equation.

Comparing with the experimental results, the availability of the principle and the validity of the model of the machine system are verified.

This HEPMSG is a new brushless self-excited and self-regulated generator, which is suitable for an independent power source.

Unlike the existing hybrid excitation permanent magnet machine, this HEPMSG utilized the inherent tooth harmonic EMF of the rotor to adjust the air-gap magnetic field of the permanent magnet machine.

The purpose of this paper is to investigate the use of hybrid‐excitation solutions, using contemporaneously permanent magnets and field coils, for DC machines intended to operate as the core of high‐reliability drives in critical applications supplied by batteries (e.g. fire‐extinguishing pumps, smoke blowers, etc.) where a roughly constant speed is required and a minimal use of electronic devices is prescribed to improve overall dependability.

A high‐reliability hybrid‐excitation DC motor, initially designed basing on theoretical considerations, is then analyzed using purposely developed 2D and 3D finite element method (FEM) electromagnetic models under static, dynamic, healthy, and faulty conditions.

The simulation results confirm that properly designed drives employing hybrid‐excitation DC motors may constitute an effective solution for applications requiring a very high reliability under DC supply with limited speed regulation capability.

The methodology employed exhibits the usual limits concerning the accuracy of FEM analysis: hysteresis is neglected, 2D simulations neglect axial component of fields, in 2D dynamic analysis the electrically discontinuous laminated cores are modeled as orthotropic continuous parts, commutator operation is approximated by means of a position‐dependent resistors network, and the excitation current provided by choppers is approximately considered as constant.

Hybrid excitation DC motors, which may be easily manufactured using existing facilities and mature technologies, might provide an interesting solution for emergency drives requiring minimal regulation capabilities and very high reliability under direct DC supply.

Hybrid excitation is not much investigated in the literature especially for DC motors, although such solution may result potentially interesting especially when a limited flux adjustment capability is required.

In order to keep the advantages of PM generators and eliminate its disadvantage – difficulty in regulating the magnetic field, hybrid excitation is an effective way. The purpose of this paper is to propose a novel way to achieve hybrid excitation by use of tooth harmonic field.

Unlike weakening the tooth harmonics field and EMF in traditional machines, in this paper the tooth harmonics field is proposed to form a novel hybrid excitation permanent magnet synchronous generator (HEPMSG).

The generation mechanism of tooth harmonic electromotive force (EMF) of rotor winding is introduced, and its influencing factors are discussed in detail. The matching design of tooth harmonic winding and field winding for maximum output field current of tooth harmonic excitation system is analyzed.

This machine can achieve not only effective adjustment of the air-gap magnetic field, but also elimination of the brushes and slip rings.

Unlike weakening the tooth harmonics field and EMF in traditional machines, in this paper the tooth harmonics filed is proposed to form a novel hybrid excitation PM synchronous generator. This machine can achieve not only effective adjustment of the air-gap magnetic field, but also elimination of the brushes and slip rings.

The purpose of this paper is to present an analytical modeling based on lumped parameter magnetic circuits of a hybrid excitation synchronous machine. The model is first established and compared with 3D finite elements analysis and measurements. It is then used to optimise hybrid excitation effectiveness.

The machine studied, which has a 3D structure, requires the use of 3D finite elements method. The 3D FEA tool is still time‐consuming, which limits its use in optimal design process. To overcome this limitation the paper investigates an analytical modeling based on lumped parameter magnetic circuits. The developed model is then used in an optimisation procedure.

The machine presented has an original structure. It has been subject to a patent protection. The operating principle of this structure has been presented and optimisation of hybrid excitation effectiveness has been investigated. Double excitation allows one to control air gap flux while reducing permanent magnets' demagnetisation risk.

The paper presents an original structure with true field regulation capability. The principle of operation has been presented. A prototype has been built and tested. The paper also presents a 3D finite elements analysis of this machine and an analytical modelling.

To address the issues of the insufficient output torque associated with the application of intensifying-flux permanent magnet (PM) machines in electric vehicles, this paper aims to propose an intensifying-flux hybrid excitation PM machine. It is possible to adjust the air gap magnetic field by adjusting the field current in the excitation winding, thereby increasing the torque output capability and speed range of the machine.

First, a novel intensifying-flux hybrid excited permanent magnet synchronous machine (IF-HEPMSM) is proposed on the basis of intensifying-flux permanent magnet synchronous machine (IF-PMSM) and an equivalent magnetic circuit model is established. Second, the tooth width and yoke thickness of the machine stator are optimized to ensure the overload capacity of the machine while effectively improving the wide flux regulation range. Furthermore, the electromagnetic characteristics of the IF-HEPMSM are investigated and compared with the IF-PMSM and conventional permanent magnet synchronous machine (PMSM) by using finite element simulations.

The i_d of IF-HEPMSM and IF-PMSM is greater than zero low-speed magnetizing current. And the flux-weakening current of the IF-HEPMSM is 18% and 3% smaller than of the conventional PMSM and IF-PMSM.

Aiming at the problems of IF-PMSM applied to electric vehicles, this paper proposes an IF-HEPMSM. The air gap magnetic field is adjusted by controlling the current of the excitation winding to improve the reliability of the machine. Therefore, the IF-HEPMSM combines the advantages of high-power density and high efficiency of the PMSM and the controllable magnetic field of the electro-excitation machine, which is of great engineering value when applied in the field of electric vehicles.

The proposed IF-HEPMSM offers better flux regulation capability with electromagnetic characteristics analysis and maps of dq-axis current as compared to IF-PMSM and conventional PMSM. Moreover, the improvement of the torque can make up for the shortcomings of the insufficient torque output capability of the IF-PMSM.

When solving the cogging torque of complex electromagnetic structures, such as consequent pole hybrid excitation synchronous (CPHES) machine, traditional methods have a huge computational complexity. The notable feature of CPHES machine is the symmetric range of field-strengthening and field-weakening, but this type of machine is destined to be equipped with a complex electromagnetic structure. The purpose of this paper is to propose a hybrid analysis method to quickly and accurately solve the cogging torque of complex 3D electromagnetic structure, which is applicable to CPHES machine with different magnetic pole shapings.

In this paper, a hybrid method for calculating the cogging torque of CPHES machine is proposed, which considers three commonly used pole shapings. Firstly, through magnetic field analysis, the complex 3D finite element analysis (FEA) is simplified to 2D field computing. Secondly, the discretization method is used to obtain the distribution of permeance and permeance differential along the circumference of the air-gap, taking into account the effect of slots. Finally, the cogging torque of the whole motor is obtained by using the idea of modular calculation and the symmetry of the rotor structure.

This method is applicable to different pole shapings. The experimental results show that the proposed method is consistent with 3D FEA and experimental measured results, and the average calculation time is reduced from 8 h to 4 min.

This paper proposes a new concept for calculating cogging torque, which is a hybrid calculation of dimension reduction and discretization modules. Based on magnetic field analysis, the 3D problem is simplified into a 2D issue, reducing computational complexity. Based on the symmetry of the machine structure, a modeling method for discretized analytical models is proposed to calculate the cogging torque of the machine.

This paper aims to present an overview of permanent magnet linear flux-switching machines (PMLFSM), field excited LFSM and hybrid excited LFSM (HELFSM) topologies as presented in literature for transportation systems such as high-speed trains and maglev systems.

The structural designs of different configurations are thoroughly investigated, and their respective advantages and disadvantages are examined. Based on the geometry and excitation sources, a detailed survey is carried out. Specific design and space issues, such as solid and modular structures, structure strength, excitation sources placement, utilization of PM materials, and flux leakage are investigated.

PMLFSM provide higher power density and efficiency than induction and DC machines because of the superior excitation capability of PMs. The cost of rare-earth PMs has risen sharply in the past few decades because of their frequent use, so the manufacturing cost of PMLFSM is increasing. Owing to the influence of high-energy PMs and magnetic flux concentration, the efficiency and power density are higher in such machines. PM is the only excitation source in PMLFSM and has constant remanence, limiting its applications in a wide speed operation range. Therefore, the field winding is added in the PMLFSM to flexibly regulate the magnetic field, making it a hybrid excited one. The HELFSM possess better flux linkage, high thrust force density and better flux controlling ability, leading to a wide speed range. However, the HELFSM have problems with the crowded mover, as PM, field excited and armature excitation are housed on a short mover. So, for better performance, the area of each excitation component has to compete with each other.

Transportation of goods and people by vehicles is becoming increasingly prevalent. As railways play a significant role in the transportation system and are an integral part of intercity transportation. So, this paper presents an overview of various linear machines that are presented in literature for rail transit systems to promote sustainable urban planning practices.

Permanent magnet (PM) electrical machines are becoming one of the most popular type of the machines used in electrical vehicle drive applications. The main drawback of permanent magnet machines, despite obvious advantages, is associated with the flux control capability, which is limited at high rotor speeds of the machine. This paper aims to present a new arrangement of permanent magnets and flux barriers in the rotor structure to improve the field weakening control of hybrid excited machines. The field weakening characteristics, back-emf waveforms and efficiency maps of this novel machine have been reported.

In the study, finite element analysis was used to perform simulation research. Then, based on the simulation studies, an experimental model was built. The paper also presents selected experimental results.

Obtained results show that the proposed machine topology and novel control strategy can offer an effective flux control method allowing to extend the maximal rotational speed of the machine at constant power range.

The proposed solution can be used in electric vehicles drive to extend its torque and speed range.

The paper presents original design and results of research on a new solution of a hybrid excited machine with magnetic barriers in a rotor.

The purpose of this paper is to analyze electromagnetic performance and develop an analytical approach to find the suitable coil combination and no-load flux linkage of the proposed hybrid excited consequent pole flux switching machine (HECPFSM) while minimizing the drive storage and computational time which is the main problem in finite element analysis (FEA) tools.

First, a new HECPFSM based on conventional consequent pole flux switching permanent machine (FSPM) is proposed, and lumped parameter magnetic network model (LPMNM) is developed for the initial analysis like coil combination and no-load flux linkage. In LPMNM, all the parts of one-third machine are modeled which helps in reduction of drive storage, computational complexity and computational time without affecting the accuracy. Second, self and mutual inductance are calculated in the stator, and dq-axis inductance is calculated using park transformation in the rotor of the proposed machine. Furthermore, on-load performance analysis, like average torque, torque density and efficiency, is done by FEA.

The developed LPMNM is validated by FEA via JMAG v. 19.1. The results obtained show good agreement with an accuracy of 96.89%.

The proposed HECPFSM is developed for high-speed brushless AC applications like electric vehicle (EV)/hybrid electric vehicle (HEV).

The proposed HECPFSM offers better flux regulation capability with enhanced electromagnetic performance as compared to conventional consequent pole FSPM. Moreover, the developed LPMNM reduces drive storage and computational time by modeling one-third of the machine.

This paper aims to further develop stator permanent magnet (PM) type memory machines by providing generalized design guidelines for double-stator memory machines (DSMMs) with hybrid PMs. This paper discusses the design experience of DSMMs and presents a comparative study of radial magnetization (RM) and circumferential magnetization (CM) types.

It begins with an introduction to RM and CM operating principles and magnetization mechanisms. Then, a comparative study is conducted for one of the RM-DSMM rotor pole pairs, inner and outer stator clamping angles and low coercive force PMs thickness. Finally, the two machines’ finite element simulation performance is compared. The validity of the proposed machine structure is demonstrated.

In this paper, the double-stator structure is extended to parallel hybrid PM memory machines, and two novel DSMMs with RM and CM configurations are proposed. Two types of DSMMs have PMs and magnetizing windings on the inner stator and armature windings on the outer stator. The main difference between the two is the arrangement of PMs on the inner stator.

Conventional stator PM memory machines have geometrical space conflicts between the PM and armature windings. The proposed double-stator structure can alleviate these conflicts and increase the torque density accordingly. In addition, this paper contributes to comparing the arrangement of hybrid PMs for DSMMs.