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This paper aims at the improvement of the cost‐effectiveness of brushless DC motor (BDCM) drives integrated in electric and hybrid propulsion systems.

The cost‐effectiveness improvement is gained through the reduction of the topology of the inverter in the armature which turns to have two legs (four switches) rather than three legs (six switches) in conventional inverters. This has been made possible thanks to the availability of the battery pack in automotive applications.

It has been found that the four‐switch three‐phase inverter (FSTPI) fed BDCM drive has almost the same performance as the six‐switch three‐phase inverter (SSTPI) fed BDCM.

This works should be extended by an experimental validation of the established results.

The reduction of the topology of the inverter in the armature of the BDCM opens up crucial cost benefits especially in large‐scale production industries, such as the automotive one.

The implementation of a simple self‐control strategy in a FSTPI fed BDCM drive yields almost the same dynamic and steady state performance as those obtained by a SSTPI fed BDCM drive. An analytical assessment of the steady state features of the FSTPI‐fed BDCM drive has been confirmed by simulation.

This study seeks to examine the analysis and control of a three‐switch three‐phase inverter (TSTPI)‐fed brushless DC motor (BDCM) as well as the comparison of its performance with those yielded by six‐switch three‐phase inverter (SSTPI)‐fed BDCM drives.

The analysis of the six operating sequences of the TSTPI‐fed BDCM drive followed by the implementation of a dedicated self‐control strategy in such a drive and the comparison of its performance with those given by an SSTPI‐fed BDCM drive.

The dedicated self‐control strategy required the integration of a torque loop in the implementation scheme in order to reduce torque ripple amplitude during sequence‐to‐sequence commutations. It has been shown that the TSTPI‐fed BDCM offers high performances which are almost the same as those of the SSTPI‐fed BDCM.

This work should be extended by building a test bench made up of a TSTPI‐fed BDCM and the comparison between simulation results and experimental ones.

A 50 per cent reduction in cost and compactness, and a 50 per cent increase in reliability make the TSTPI an interesting candidate especially in large‐scale production applications such as the automotive industries.

The paper proposes an approach to improve the cost‐effectiveness and the volume‐compactness of BDCM drives which represents a crucial challenge in electric and hybrid propulsion systems. It is the best solution compared with the conventional SSTPI and the four‐switch three‐phase inverter.

The purpose of this paper is to discuss the design of concentrated winding permanent magnet (PM) machines dedicated to propulsion applications considering both surface‐mounted and flux‐concentrating arrangements of the PMs.

Following the selection of a suitable distribution of the concentrated winding, a derivation of the machine inductances is carried out in order to highlight the increase in the flux‐weakening range gained through the substitution of distributed windings by concentrated ones. Then, mmf and finite element analysis are carried out in order to investigate the air gap flux density and the torque production capability of both surface‐mounted and flux‐concentrating PM machines.

The paper finds that, although both machines provide almost the same average torque, the surface‐mounted PM machine offers lower torque ripple with respect to the flux‐concentrating arrangement: a crucial benefit in electric and hybrid propulsion systems.

The research should be extended to the comparison of the obtained results related to the torque production capability with experimental measurements.

An increase in the efficiency associated with the extension of the flux‐weakening range and a reduction of the volume make the concentrated winding PM machines interesting candidates, especially in large‐scale production applications such as the automotive industry.

The paper proposes an approach to design and performance investigation of concentrated winding PM machines considering both surface‐mounted and flux‐concentrating arrangements of the PMs.

The purpose of this paper is to propose an approach to teach to post‐graduate students the basis of hybrid propulsion systems (HPS) with emphasis on their electric drive unit.

Following the introduction of the basic topologies of HPS, a case study is focused with an analysis of its current features. Of particular interest, those related to the flux‐weakening range extension and the cost‐effectiveness improvement are rethought in an attempt to stimulate the innovative capabilities of the students.

The adopted methodology has been integrated in a master course and has been found attractive and informative by the students.

The proposed teaching approach should be complemented by appropriate laboratory courses.

Thanks to the proposed methodology, the basis of HPS is no longer restricted to a selected population of the electrical engineering community.

This paper deals with the analysis, the modeling, the control and the fault‐tolerance capability of a three‐switch inverter (TSI, also known delta‐inverter) fed fractional‐slot six‐phase brushless DC motor (BDCM) drive.

Following the presentation of the advantages of multi‐phase fractional‐slot brushless machines and the possibility of their association to TSI, the analysis of the operating sequences as well as the modeling of a TSI fed six‐phase BDCM drive are developed. Then, a dedicated control strategy of such a drive is synthesized. Finally, a case study is simulated considering both transient behaviour during the start‐up of the BDCM as well as a steady‐state one under healthy and faulty operations.

It has been found that the 60‐electrical degree shift between the six phases of the BDCM makes it simple to achieve its operating sequences with its armature fed by a TSI, considering a suitable anti‐parallel connection of the six phases.

Crucial cost benefits associated with improved compactness, reliability, and fault‐tolerance capability could be gained thanks to the integration of TSI fed six‐phase BDCM drives in large‐scale production industries, such as the automotive one.

The paper proposes an analysis of the operating sequences as well as the fault‐tolerance capability of TSI fed six‐phase BDCM drives.

This paper aims at the derivation of an accurate reluctance model of a transverse flux permanent magnet machine (TFPM) and its validation by finite element analysis (FEA).

Analytical prediction of the different reluctances in the core, the permanent magnets, and the air. These reluctances characterize the paths of both main and leakage fluxes. Then, a validation of the proposed reluctance model is carried out using FEA. An interesting application of the proposed reluctance consists in the assessment of the TFPM torque production capability.

The torque yielded by the reluctance model of the TFPM and the one computed using 3D‐FEA are in good agreement. This result is of great importance in so far as the CPU time required for 3D‐FEA computation is much more higher than the one consumed in the resolution of the reluctance model.

Further validation of the results yielded by the proposed reluctance model through their comparison with experimental measurements shall be treated in the future.

The proposed reluctance model is of great interest for the TFPM sizing. It could be useful in the pre‐design procedure of the machine.

The paper proposes a new reluctance model where the leakage fluxes are accurately predicted.

The purpose of this paper is to introduce an aid for teaching transverse flux permanent magnet machines (TFPMs) with emphasis on their torque production.

The Lorentz force law is applied to fictitious current loops emulating the permanent magnets (PMs) mounted on the rotor according to different arrangements; the air gap flux density is created by the armature current.

Implemented in a master lecture on special AC machines, the proposed approach has revealed a renewed interest in electromagnetic fundamentals for pedagogical purposes. It makes simple the explanation of the principle of operation of a class of AC machines reputed by the complexity of their magnetic circuits. The latter incorporates axially stacked decoupled sub-circuits, one per phase generating alternating magnetic fields. More specifically, there is common air gap, shared by the machine phases, in which a rotating magnetic field is created by the superposition of the PM contribution and the armature one.

Accounting for the complexity of the magnetic circuits and the three-dimensional (3D) flux paths characterizing TFPMs, a 3D finite element analysis (FEA) is required for the validation of the analytical predictions. Nevertheless, such a 3D FEA validation is far from being obvious to be carried on within a master lecture.

While the basis of Lorentz forces resulting from fictitious current loops emulating PMs has been considered in some referenced papers, its simple and pedagogical application to assess the torque production of several TFPM concepts represents the added value of the present paper.

The purpose of this paper is to deal with several approach to recover the torque production capability of a five phase double-layer fractional-slot PM machine under faulty operation. The considered fault is an open-circuit coil in a given phase.

In a first step, the mean futures, such as the phase back-EMFs and the electromagnetic torque, are computed by finite element analysis under healthy operation, and are taken as references. Then, they are investigated, under a faulty coil, for different approaches to recover the torque production capability.

A comparison of the potentialities of the torque recovery approaches has clearly highlight the superiority of the approach consisting in the re-adjustment of the current initial phases, in an attempt to equilibrate the resulting air gap MMF.

This work should be extended by an experimental validation of the predicted results regarding the back-EMFs and the electromagnetic torque.

The investigation of the considered five phase fractional-slot PM machine under faulty operation should be extended to several faulty scenarios in order to fulfill the requirements of many applications such as the propulsion systems.

The paper proposes different approaches to recover the torque production capability of a five phase fractional-slot PM machine under faulty operation.

The purpose of this paper is to describe the implementation of a direct torque control strategy dedicated to three‐switch three‐phase delta‐shaped inverter (TSTPI) fed induction motor drives as well as the comparison of its performance with those yielded by six‐switch three‐phase inverter (SSTPI) fed induction motor drives under the Takahashi DTC strategy.

Referring to the asymmetrical stator voltage vectors and in order to reach high dynamic with low ripple of the electromagnetic torque response, the design of the vector selection table should include virtual voltage vectors by the subdivision of each sector into two equal sub‐sectors.

It has been shown that the implementation of the proposed DTC strategy in TSTPI‐fed induction motor drives leads to higher transient behaviour and better steady‐state features than those exhibited by the Takahashi DTC strategy implemented in SSTPI‐fed induction motor drives.

The research should be extended to a comparison of the obtained simulation results with experimental measurements.

A 50 per cent reduction of cost and compactness associated with a 50 per cent increase of reliability makes the TSTPI an interesting candidate, especially in large‐scale production applications such as the automotive industry.

The paper proposes an approach to improve the cost‐effectiveness, the compactness and the reliability of TSTPI‐fed induction motor drives, which represents a crucial benefit in electric and hybrid propulsion systems.

The purpose of this paper is to propose an approach to improve the torque production capability of fractional slot permanent magnet machines.

Following an analytical formulation of the electromagnetic torque, two optimization criteria are selected: the maximization of the average torque and the minimization of the torque ripple. For the sake of a simple analysis, the proposed approach assumes that the effects of the machine circumferential and radial parameters, on the torque production capability, are almost decoupled, so that their sizing optimization could be carried out separately.

The torque production capability of the optimized machine has been confirmed by finite element analysis, which confirms the appropriateness of the proposed sizing approach.

The obtained results should be validated by experiments carried out on a prototype.

The proposed approach has been carried out thanks to the introduction of the torque average value and ripple amplitude iso‐2D curves for circumferential parameters and iso‐3D surfaces for radial ones.