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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.

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 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.

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 to propose a method to evaluate the information obtained on harmonics calculations and to estimate the precision of results using finite element method for an innovative motor topology in which some well-known meshing rules are difficult to apply.

The same magnetostatic problem is solved with several mesh sizes using both scalar and vector potentials magnetics formulations on a complex topology, an axial claw pole motor (ACPM). The proposed method lies in a comparison between the two weak formulations to determine what information is obtained on harmonics calculations and to estimate its precision. Moreover, an original mesh method is applied in the air gap to improve the numerical results.

The precision on harmonics calculations using finite element method on an ACPM is estimated. For the proposed motor and mesh, only the mean value (even with large mesh) and the first harmonic (with fine mesh) of torque are calculated with a good accuracy. This results confirm that the non-respect of the meshing rules have a strong impact on the results and that scalar and vector potentials magnetics formulations do not give exactly the same results. Before using torque harmonics values in vibration calculations, a finite element model has to be validated by using both fomulations.

This method is time-consuming and only applied on an ACPM in this work.

The axial claw pole motor, for which the classic meshing rules cannot be applied, is a complex topology very under-studied. To improve the calculation of space harmonics, the authors proposed to split the airgap into four parts. Then in the two central parts, the meshing step of the structured mesh is equal to the rotating step.

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 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.

The purpose of this paper is to develop a novel coupled analysis method for synchronous rectification alternators.

An ideal diode module is embedded in a rectification circuit. The resistance of the diode module is set such that it is equal to the on-resistance of the MOS-FET modules in the generation mode. In a mode without power generation, the motor voltage is less than the bus voltage; a sufficiently large value is defined for simulating the infinite resistance.

Because there is no need to decide the switch timing in advance, only one round of coupled analysis is needed to evaluate the synchronous rectification alternators.

As limited case study is denoted in this paper, much more case studies are needed to be discussed.

By using the proposed method, it can be fulfilled that generation characteristic of automotive alternators can be evaluated without using the control simulation or pre-conducted analysis to decide the switch timing.

By using the proposed method, it can be fulfilled that generation characteristic of automotive alternators can be evaluated without using the control simulation or pre-conducted analysis to decide the switch timing.

In the proposed methods, the definition of diode module differs from that of a conventional coupled analysis.