Computation of wound rotor induction machines based on coupled finite elements and circuit equation under a first space harmonic approximation

The paper presents a fast method to compute wound rotor induction machines in steady state. Coupled time-harmonic FE-circuit equation are used under a first space harmonic approximation for the air-gap magnetic field. It is shown that only 4 magnetostatic FE computations are necessary to determine the machine performances for any slip value. The performances comparison to a conventional complex magnetodynamic and time stepping FE analyses show the effectiveness of the proposed approach

Non-linear circuit based model of PMSM under inter-turn fault: a simple approach based on healthy machine data

The paper proposes a fast dynamic mathematical model to evaluate the performances of saturated permanent magnet synchronous machines (PMSM) under stator winding’s inter turn fault. The parameters of the model can be determined using only manufacturer’s data of the healthy machine. Two surface mounted PMSM have been considered to investigate the validity of the proposed approach; with distributed and concentrated winding. It has been shown that the proposed model predicts the fault current with a reasonable accuracy compared to the non-linear Finite Elements analyses and to the experimental results. This model can be incorporated in a global simulation environment of power electronic of electrical device since the computation time is very short

Modeling and analysis of eddy current losses in permanent magnet machines with multi-stranded bundle conductors

This paper investigates the influence of eddy current losses in multi-stranded bundle conductors employed in out-runner permanent magnet machines, by adopting an analytical model. The analytical model is based on a sub-domain field model that solves the two-dimensional magnetostatic problem using the separation of variables technique for each of the non-magnetically permeable machine sub-domains: PM, airgap and slots. The validity and accuracy of the proposed model is verified using finite element analysis and then used to investigate the eddy current losses. The machine considered for the analysis has 36 slots and 42-poles previously designed for aircraft taxiing. The influence of the number of turns and the conductor cross-sectional area are investigated. It is shown that efficiency can be improved considerably by the choice of multi- stranded bundle conductors

Model predictive direct torque control and fuzzy logic energy management for multi power source electric vehicles

This paper proposes a novel Fuzzy-MPDTC control applied to a fuel cell battery electric vehicle whose traction is ensured using a permanent magnet synchronous motor (PMSM). On the traction side, model predictive direct torque control (MPDTC) is used to control PMSM torque, and guarantee minimum torque and current ripples while ensuring satisfactory speed tracking. On the sources side, an energy management strategy (EMS) based on fuzzy logic is proposed, it aims to distribute power over energy sources rationally and satisfy the load power demand. To assess these techniques, a driving cycle under different operating modes, namely cruising, acceleration, idling and regenerative braking is proposed. Real-time simulation is developed using the RT LAB platform and the obtained results match those obtained in numerical simulation using MATLAB/Simulink. The results show a good performance of the whole system, where the proposed MPDTC minimized the torque and flux ripples with 54.54% and 77%, respectively, compared to the conventional DTC and reduced the THD of the PMSM current with 53.37%. Furthermore, the proposed EMS based on fuzzy logic shows good performance and keeps the battery SOC within safe limits under the proposed speed profile and international NYCC driving cycle. These aforementioned results confirm the robustness and effectiveness of the proposed control techniques.Web of Science2215art. no. 566

Les engrenages magnétiques et leur association aux machines électriques tournantes

International audienc

Modélisation électromagnétique et thermique des moteurs à induction, en tenant compte des harmoniques d'espace

This work is interested in the study of the electromagnetic and thermal behaviors of the induction motor. A state of the art is initially drawn up, where we have presented and discussed the current methods dealing with electromagnetic and thermal modeling of induction motors. An electromagnetic model, that uses the 2D complex finite element method to solve the field equations, is developed. The rotor movement is accounted for by coupling the air gap field, for each space harmonic, using the double air gap method. The superposition principle permits the determination of the final solution. To deal with non linear problems, an approach that introduces equivalent reluctivities, is proposed. We have assumed that the saturation is only due to the first space harmonic. A thermal model is elaborated by using the nodal method. The machine is cut up into 11 cylindrical lumped elements, the thermal model represents the juxtaposition of these lumped elements. The electromagnetic and thermal models are, weakly, coupled together for a more precise determination of the temperature distribution inside the motor. ln the validation phase of our work, we have designed a test bench that allows specific torque and temperature measurements. The comparison of the calculations and the measurements is satisfactory.Ce travail s'intéresse à l'étude des comportements électromagnétique et thermique du moteur à induction. Un état de l'art, où les méthodes courantes de modélisation électromagnétique et thermique du moteur à induction sont abordées, est d'abord dressé. Un modèle électromagnétique qui utilise la résolution par éléments finis 2D des équations du champ, en adoptant la représentation complexe, est développé. La prise en compte du mouvement du rotor par le couplage des champs dans l'entrefer, pour chaque harmonique d'espace, se fait par la méthode du double entrefer. Le principe de superposition permet de déterminer la solution finale. Afin de traiter les problèmes non linéaires, nous avons proposé une approche qui permet d'introduire des réluctivités équivalentes. Nous avons supposé que la saturation est due au seul premier harmonique d'espace. Un modèle thermique utilisant la méthode nodale est élaboré. La machine est découpée en 11 blocs élémentaires de forme cylindrique; le modèle global de la machine est composé de la juxtaposition des circuits thermiques correspondant à chaque bloc. Un couplage, au sens faible, des modèles électromagnétique et thermique est réalisé pour une détermination plus fine de la distribution de la température dans le moteur. Dans la phase de validation de nos calculs, nous avons conçu un banc d'essais qui permet des mesures spécifiques du couple et des températures. Les résultats des calculs, comparés aux mesures effectuées, sont satisfaisants

Influence of the shape of the current on AC losses in superconducting tube and coil.

LGEP 2011 ID = 951International audienc