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The purpose of this paper is to discuss the performance of a proposed machine design for an in‐wheel motor with the required torque‐speed characteristic.

Calculation of the winding factor of the machine with the star of slots theory is performed first. The field weakening capability of the machine is investigated and the operating speed range is determined. The tooth contour modeling method for calculating the performance of the machine with a limited number of elements is introduced. The method is used to construct two models of different complexity and the results obtained with the models are compared with the results obtained by finite element models.

The 14 pole 12 slot in‐wheel PMSM discussed in this paper is able to meet the stringent performance requirements. The results obtained with the tooth contour models show good agreement with the results obtained with finite element models despite the limited number of elements. Increasing the number of elements in the model allows for modeling of armature reaction and increases the accuracy of the model.

This work can be continued with investigating the possibilities to model the armature reaction more accurately.

This paper proposes a modeling method which accurately describes the performance of a PMSM with limited number of elements. With this method, the calculation procedure can be easily used for optimization of the machine design.

This paper is aimed at investigating the potential advantages of flux‐switching machines (FSM) compared to permanent magnet synchronous machines (PMSM), particularly for the applications of electric vehicle traction.

A 12‐slot 14‐pole PMSM designed for an in‐wheel traction application is chosen for the comparison. With the same volume constraint, three 12/14 FSM structures are created. Both the PMSM and the three FSM structures are modeled using the software Flux. Based on these models, finite element analyses (FEA) are performed, and the results are compared in terms of open‐circuit back electromotive force (EMF), electrical loading capability, and thermal conditions.

Within the same volume constraint, a 12/14 FSMs can achieve the maximum torque higher than the one of 12/14 PMSM. This conclusion is drawn based on the observed facts that at the same rotor speed, a larger open‐circuit back EMF is induced in the FSM, while a larger electrical loading is also allowed in this machine, compared to the PMSM. In addition, the risk of demagnetization during the process of field weakening proves to be lower in FSMs than PMSMs. This advantage suggests a potentially wide constant power speed range (CPSR) of FSMs, which is especially beneficial in automotive applications.

This research can be continued with investigating the field weakening capability and iron losses of FSMs.

This paper proposed two optional structures of FSMs to reduce the amount of permanent magnets. It also highlighted the effectiveness of FSMs in cooling these magnets.

This paper aims to reviewed analytical methodologies, i.e. lumped parameter magnetic equivalent circuit (LPMEC), magnetic co-energy (MCE), Laplace equations (LE), Maxwell stress tensor (MST) method and sub-domain modelling for design of segmented PM(SPM) consequent pole flux switching machine (SPMCPFSM). Electric machines, especially flux switching machines (FSMs), are accurately modeled using numerical-based finite element analysis (FEA) tools; however, despite of expensive hardware setup, repeated iterative process, complex stator design and permanent magnet (PM) non-linear behavior increases computational time and complexity.

This paper reviews various alternate analytical methodologies for electromagnetic performance calculation. In above-mentioned analytical methodologies, no-load phase flux linkage is performed using LPMEC, magnetic co-energy for cogging torque, LE for magnetic flux density (MFD) components, i.e. radial and tangential and MST for instantaneous torque. Sub-domain model solves electromagnetic performance, i.e. MFD and torque behaviour.

The reviewed analytical methodologies are validated with globally accepted FEA using JMAG Commercial FEA Package v. 18.1 which shows good agreement with accuracy. In comparison of analytical methodologies, analysis reveals that sub-domain model not only get rid of multiples techniques for validation purpose but also provide better results by accounting influence of all machine parts which helps to reduce computational complexity, computational time and drive storage with overall accuracy of ∼99%. Furthermore, authors are confident to recommend sub-domain model for initial design stage of SPMCPFSM when higher accuracy and low computational cost are primal requirements.

The model is developed for high-speed brushless AC applications.

The SPMCPFSM enhances electromagnetic performance owing to segmented PMs configuration which makes it different than conventional designs. Moreover, developed analytical methodologies for SPMCPFSM reduce computational time compared with that of FEA.

The purpose of this paper is to comparatively study the conventional, i.e. single magnet, and novel hybrid-magnet switched-flux permanent-magnet (HMSFPM) machines.

The HMSFPM machines utilize two magnet types, i.e. low-cost ferrites and NdFeB. Thus, a set of magnet ratios (?), defined as the quotient of the NdFeB volume to the total PM volume, is introduced. This allows any desired performance and cost trade-off to be designed. Series- and parallel-excited magnet configurations are investigated using 2-dimensional finite element analysis.

The torque of the HMSFPM machines is lower than the NdFeB SFPM machine but the flux-weakening performance is improved for similar machine efficiency. If the machine dimensions are unconstrained, the HMSFPM machines can have the same torque for reduced material costs and a moderate increase in machine dimensions. Ferrite SFPM machines have the lowest cost for the same torque but a significant increase in machine dimensions is required. Finally, the series-excited HMSFPM machine is the preferred over the parallel-excited HMSFPM machine because it has superior demagnetization withstand capability.

Mechanical and winding eddy current losses are not considered in the efficiency map calculations.

The NdFeB SFPM, ferrite SFPM, series-excited HMSFPM, and the parallel-excited HMSFPM machines are compared for their electromagnetic performance, flux-weakening, PM demagnetization, efficiency, and material costs.

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.

The purpose of this paper is to investigate an alternative simplified analytical approach for the design of electric machines. Numerical-based finite element method (FEM) is a powerful tool for accurate modelling and electromagnetic performance analysis of electric machines. However, computational complexity, magnetic saturation, complex stator structure and time consumption compel researchers to adopt alternate analytical model for initial design of electric machine especially flux switching machines (FSMs).

In this paper, simplified lumped parameter magnetic equivalent circuit (LPMEC) model is presented for newly developed segmented PM consequent pole flux switching machine (SPMCPFSM). LPMEC model accounts influence of all machine parts for quarter of machine which helps to reduce computational complexity, computational time and drive storage without affecting overall accuracy. Furthermore, inductance calculation is performed in the rotor and stator frame of reference for accurate estimation of the self-inductance, mutual inductance and dq-axis inductance profile using park transformation.

The developed LPMEC model is validated with corresponding FEA using JMAG Commercial FEA Package v. 18.1 which shows good agreement with accuracy of ∼98.23%, and park transformation precisely estimates the inductance profile in rotor and stator frame of reference.

The model is developed for high-speed brushless AC applications.

The proposed SPMCPFSM enhance electromagnetic performance owing to partitioned PMs configuration which make it different than conventional designs. Moreover, the developed LPMEC model reduces computational time by solving quarter of machine.

The purpose of this paper is to investigate and compare the influence of end-effect on the torque-speed characteristics of three conventional switched flux permanent magnet (SFPM) machines having different stator/rotor pole combinations, i.e. 12/10, 12/13 and 12/14 as well as three novel topologies with less permanent magnets (PMs), i.e. multi-tooth, E-core and C-core.

SFPM machines combine the advantages of simple and robust rotor and easy management of the temperature due to the location of the PMs and armature windings on the stator. However, due to spoke location of the PMs a large flux leakage in the end region, i.e. end-effect, can be observed which could result in a large reduction in the electromagnetic performance. Therefore, the influence of end-effect on the torque-speed characteristics is investigated. 3D-finite element analyses (FEA) results are compared with their 2D-FEA counterparts in order to account for the end-effect influence.

It has been concluded that due to end flux leakage, lower torque capability in the constant torque region is observed in the six machines. However, improved flux-weakening capability in the conventional machines can be exhibited at high current levels, whereas due to the large inductance lower power capability in the multi-tooth, E-core and C-core machines is obtained.

The influence of temperature rise on the performance is not included.

This paper has analysed the influence of end-effect on the torque-speed characteristics of several SFPM machines.

Field excited flux switching machines (FEFSM) are preferred over induction and synchronous machines due to the confinement of all excitation sources on the stator leaving a robust rotor. This paper aims to perform coupled electromagnetic thermal analysis and stress analysis for single phase FEFSM as, prolonged high-speed operational time with core and copper losses makes it prone to stress and thermal constraints as temperature rise in machine lead to degraded electromagnetic performance whereas the violation of the principle stress limit may result in mechanical deformation of the rotor.

This paper presents the implementation of coupled electromagnetic-thermal and rotor stress analysis on single-phase FEFSM with non-overlap winding configurations using finite element analysis (FEA) methodology in JMAG V. 18.1. three-dimensional (3D) magnetic loss analysis is performed and extended to 3D thermal analysis to predict temperature distribution on various parts of the machine whereas Stress analysis predicts mechanical stress acting upon edges and faces of the rotor.

Analysis reveals that temperature distribution and rotor stress on the machine is within acceptable limits. A maximum temperature rise of 37.7°C was noticed at armature and field windings, temperature distribution in stator near pole proximity was 35°C whereas no significant change in rotor temperature was noticed. Furthermore, principal stress at the speed of 3,000 rpm and 30,000 rpm was found out to be 0.0305 MPa 3.045 MPa, respectively.

The designed machine will be optimized for improvement of electromagnetic performance followed by hardware implementation and experimental testing in the future.

The model is developed for axial fan applications.

Thermal analysis is not being implemented on FEFSM for axial fan applications which is an important analysis to ensure the electromagnetic performance of the machine.

The purpose of this paper is to investigate winding topologies for flux-switching motors (FSMs) with various segment-tooth combinations and different excitation methods.

For the ac winding of FSM, two winding topologies, namely the concentrated winding and the distributed winding, are compared in terms of the winding factor and efficiency. For the field winding of dc-excited FSM (DCEFSM), another two winding topologies, namely the lap winding and the toroidal winding, are compared in terms of effective coil area, end-winding length, and thermal conditions. Analytical derivation is used for the general winding factor calculation. The calculation results are validated using finite element analysis.

Winding factors can be used as an indication of winding efficiency for FSMs in the same manner as done for synchronous motors. For FSMs with concentrated windings, the winding factor increases when the rotor tooth number approaches a multiple of the stator segment number. For FSMs with certain segment-tooth combinations, e.g. 6/8, the theoretical maximum winding factor can be achieved by implementing distributed windings. Furthermore, the toroidal winding can be an efficient winding topology for DCEFSMs with large stator diameter and small stack length.

This work can be continued with investigating the variation of reluctance torque with respect to different segment-tooth combinations of FSM.

This paper proposes a general method to calculate the winding factor of FSMs using only the phase number, the stator segment number, the rotor tooth number, and the skew angle. Using this method, a table of winding factors of FSMs with different segment-tooth combinations is provided. Principle of design of FSMs with high-winding factors are hence concluded. This paper also proposed the implementation of distributed windings for FSM with certain segment-tooth combinations, e.g. 6/8, by which means a theoretical maximum winding factor is achieved. In addition, different winding topologies for the field winding of DCEFSM are also investigated.

The purpose of this chapter is to discuss operational performance as a tool for construction project success. Specifically, the chapter examines important aspects such as the definition and meaning of operational performance, operational performance objectives, operational performance indicators and the key points to increasing operational performance. This chapter emphasises the importance of operational performance in business as it plays vital role in other aspects of business or company's variables. It concludes that investment in the improvement of operational performance is very important to any successful business. The essence of operational performance is to identify problems and provide solutions to them. It is essential to know that every difficulty that is encounter in business should be picture as a chance to become better. On this note, a mentality that embraces continual improvement should be taken graciously and adopted in order to make sure that a company continue to plan for the future.