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This paper aims to propose a new topology of direct current (DC) machine using claw-pole stator to replace standard DC starter in micro-hybrid vehicles. The main interest of such a topology is the reduction of copper volume.

The design of the claw-pole machine is based on a multi-objective optimization of several topologies, based on a three-dimensional (3D) reluctance network modeling. The 3D finite element (FE) model is used to check the results of the optimization, and a prototype is manufactured and tested with satisfactory results.

The claw-pole topology with wave-shape windings allows to replace the current DC series classical starter because of to its copper volume saving.

This model is only limited to the optimization of the claw-pole stator for a fixed geometry of the rotor.

The research outcome shows that claw-pole machine can replace the series-excited DC machines of starters and at the same time achieve the same performance at reduced copper volume.

The paper deals with a new DC machine topology to reduce the copper volume through the suppression of the classical stator end-windings. The use of Claw-Pole inductors ensures this copper reduction.

This paper aims at the improvement of the generating capability of a hybrid excited brushless claw pole alternator (HEBCPA).

Following the identification of the HEBCPA influent sizing parameters, the investigation of their impact on the back‐EMF production capability is carried out considering a 3D‐finite element analysis (FEA).

The HEBCPA Back‐EMF production capability is highly affected by the variation of the influent sizing parameters. A selected combination of these parameters has led to an optimized generating capability.

An experimental validation of the generating performance computed by 3D‐FEA shall be treated in the future.

The optimized HEBCPA is of great interest for the automotive applications as well as for wind energy generating systems.

The optimized HEBCPA is a new concept that has been proposed by the authors in a recent work.

The purpose of this paper is to deal with the modeling of a claw pole alternator (CPA) by a 3D magnetic equivalent circuit (MEC) taking into account the saturation and magnetic armature reaction effects then its utilization for the prediction of the machine losses.

Following the derivation of the proposed model, it is validated experimentally at no-load and load operations. Proposed MEC is applied to the investigation of a conventional CPA losses.

The CPA efficiency is affected by different loss mechanisms. Indeed, the copper losses are dominant at lower speeds, while the iron and ventilation ones are more significant at high speeds.

An experimental validation of the losses computed by the MEC shall be treated in the future.

The CPA is equipping most if not all embedded generating systems of road vehicles. The improvement of its efficiency is of great importance.

The MEC-based prediction of the CPA losses represents the major contribution of the present work.

The purpose of this paper is to propose improvement of the generation capability of a claw pole alternator with DC excitation in the stator (CPAES) using analytical investigation based on a dedicated reluctant model.

The paper analyzes the effects of geometry and material transformations of the magnetic circuit on the generation capability of the CPAES as well as the reduction of claw‐claw leakage flux by inserting permanent magnets in between adjacent claws.

The generation capability could be improved considering the proposed geometry and material changes of the magnetic circuit of the CPAES. The inclusion of permanent magnets in between adjacent claws offers an increase of the alternator generation due to the reduction of the claw‐claw leakage flux.

The research should be extended by building a new prototype of the CPAES in order to compare analytical results and experimental ones.

A new concept with no brush‐ring for excitation and an improvement of the generation capability of the alternator make the CPAES an interesting candidate especially in large‐scale production applications such as the automotive industry.

The paper proposes a new alternator topology called claw pole alternator with DC excitation in the stator (CPAES) and an analytical approach to improve the generation capability of such a concept, which represents a crucial challenge in electric generation systems especially in automotive applications.

The purpose of the paper is to evaluate theoretically and experimentally the static and dynamic characteristics of a single‐phase claw‐pole motor using soft magnetic composite (SMC) for the stator core.

On the basis of the static characteristics, which are measured and obtained from a series of 3D FE magnetostatic solutions, the dynamic characteristics are simulated according to a proposed control strategy. The same strategy is tested in dSpace control environment. Apart from the evaluation of the prototype SMC motor, some study has been made in order to improve the existing motor design.

The static characteristics of the single‐phase claw‐pole motor have been modelled in 3D FE magnetostatic solver, where the rotor position and stator current have been changed. The characteristics compare well with the measurements, while the discrepancy with the cogging torque waveform needs further analyses and experiments to explain the real magnetization pattern of the plastic bounded ferrite magnet‐ring and the influence of magnetic hysteresis. The 3D FE magnetostatic optimization routine shows the maximum quantities for magnetic coupling and static core loss. Furthermore it is used to obtain the improved pole distribution so that the resting position of the unexcited motor co‐aligns at the position of the maximum electromagnetical torque. This is achieved by changing the angular width of claw‐poles. The specific output of the maximum coupling torque from the single‐phase claw‐pole motor can be increased from the recent 0.1 to 0.6 Nm/kg at a temperature rise of 60°. The simulations of dynamical characteristics show a good correlation with the experiments where the same control system in Simulink is applied to the prototype via dSpace. It is practically easier to implement a simple control strategy for the direct current controlled voltage source inverter. A more advantageous control system needs to be applied for the sampled current controller.

The influence of the magnetization of a multi‐pole magnet ring is not considered while computing the static characteristics in 3D FE magnetostatic solver.

The evaluation of the realistic magnetization pattern in the magnet aggravates the proper theoretical evaluation of static characteristics.

The design of a small size powder core motor is faced with the complexity of evaluating properly the static characteristics, while the magnetization pattern is not exactly known. The broad search here is for an efficient tool to visualize the output of the 3D FE optimization for an improved design.

The paper aims to present the hybrid excited claw pole generator design, simulation and experimental results. The prototype has claw poles on two rotor sections, between which an excitation coil is located. The innovation of this machine is permanent magnets location on claws of one part of the rotor. The paper presents construction of the machine and analysis of the current in the excitation control coil influence on the electromagnetic torque, cogging torque and back-emf values. Presented studies enabled the determination of the torque and the back-emf for both: the strengthening and the weakening of magnetic field.

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.

Achieved results show that the proposed machine topology allows to eliminate the disadvantages mentioned in paper, i.e. necessary to introduce special areas inside the machine to limit magnetic flux leakage or its complicated construction.

The obtained cogging torque values and back-emf pulsation are still relatively high. In the near future, some of known techniques for reducing these pulsations can be applied, including the use of magnetic wedges, changing shapes of rotor’s poles and/or skewing of permanent magnets.

The proposed solution can be used in wind turbines as a generator.

The paper presents an original design of a new construction of a hybrid-excited claw pole machine and also an excitation current influence on cogging torque and back-emf values.

Recently, considerable attention has been attracted to the development of the new concept motor for EV or HEV. Wider torque and speed controllable operating range and high efficiency under driving area are needed for traction motor. The purpose of this paper is to realize the new concept variable field flux motor with claw pole rotor and brushless robust structure for high-speed range.

In the previous paper, the authors proposed a half-wave rectified brushless variable field flux method with a diode inserted into the field winding. This paper presents a designing for a novel claw pole rotor type motor using the variable field flux method (CP-HVFM). The claw pole type rotor has simple and robust structure for high-speed operation. This paper describes a first prototype design result for CP-HVFM using 3D-FEM. And the authors report the torque and efficiency characteristic results using 3D-FEM.

The authors have studied the designing for CP-HVFM using 3D-FEM. The designed prototype CP-HVFM reached a rated power of 2 kW or more at a rated speed 1,800 rpm under design restrictions of experimental equipment and initial specifications. In addition, the authors found the ratio of the tip and root embrace of the claw pole shape for maximum average torque and minimum torque ripple. Finally, the authors revealed an influence of the armature current on the torque and the efficiency characteristic results for the designed prototype CP-HVFM using 3D-FEM.

The half-wave rectified brushless variable field flux method proved to be effective for the claw pole rotor type motor. And also the authors found the best claw pole shape for torque characteristic. This results are applied to another concept motor for EV or HEV.

This paper deals with 3D finite‐element calculation of eddy currents in the claws of a claw‐pole alternator taking the rotational geometry movement into account. Two transient edge‐based vector formulations are utilised. The reduction of the model to only one pole pitch in combination with a special boundary pairing in the air gap for the applied lock‐step method is presented. Calculations of varying material conductivity are performed with simplified end windings. The speed characteristics of the eddy currents with real conductivity and realistic end windings concludes the paper.

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.

This paper describes a thermal and electrical model, used at Robert Bosch GmbH for the design of an innovative motor for a water‐pump. In addition, it offers an example of a highly integrated mechatronic system. A bonded‐ferrite inner rotor has been developed with an integrated front centrifugal impeller which is driven by the magnetic interaction of a rotating field created by claw‐poles. The two phase unipolar coil arrangement is fed by an internal circuit using two MOSFETS controlled by the commutation signal from a bipolar Hall‐IC. This is the first mass‐production example of an electrical machine for an automotive application where the claw pole topology is used to realise the armature of the motor (i.e. the rotating field) and not the excitation field.