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The purpose of this paper is to describe the methodology adopted to design an electric motor applied to the traction of a single-seat high-performance electric vehicle. A comparative selection of topologies of electrical machines is made and then, an analytical model of the chosen layout is described. An evolutionary algorithm is used in order to find an optimized solution according to some selected performance criteria. Afterwards, the analysis of the selected design is made in a finite element simulation software. Finally, a comparison between the analytical and the finite element models results is performed.

This paper presents the analysis and the design of a ferrite permanent magnet synchronous generator (FePMSG) with flux concentration. Despite the well-known advantages of rare earth permanent magnet synchronous generators (REPMSG), the high cost of the rare earth permanent magnets represents an important drawback, particularly in competitive markets like the wind power. To reduce the cost of permanent magnet machines it is possible to replace the expensive rare earth materials by ferrite. Once ferrite has low remanent magnetization, flux concentration techniques are used to design a cheaper generator. The designed FePMSG is compared with a reference rare earth (NdFeB) permanent magnet synchronous generator (REPMSG), both with 3 kW, 220 V and 350 rpm. The results, validated with finite element analysis, show that the FePMSG can replace the REPMSG reducing significantly the active material cost.

A computer model, including analytical and FEM formulations, was developed to calculate the starting performance of synchronous motors with solid rotor salient poles. Using quasi-steady state equations, the average and the envelope of the oscillating electromagnetic torque as well as the stator rms current are calculated. With the stator current, the rotor pole losses are evaluated by FEM. The complete simulation process is performed by self-contained software composed by several computational modules properly tiled to simplify the work of a design engineer. The calculated starting performance was compared to experimental results showing satisfactory consistency.

Line-start permanent magnet motor (LSPMM) is a very attractive alternative to replace induction motors due to its very high efficiency and constant speed operation with load variations. However, designing this kind of hybrid motor is hard work and requires a good understanding of motor behavior. The calculation of load angle is an important step in motor design and can not be neglected. This paper uses the finite element method to show a simple methodology to calculate the load angle of a three-phase LSPMM combining the dynamic and steady-state simulations. The methodology is used to analyze a three-phase LSPMM.

A model allowing the simulation of induction machines with different rotor bars configurations is presented. The electrical machine is modeled by using two-dimensional (2-D) finite-element method and its equations are directly coupled with those of the circuit. A general and new contribution is added for the consideration of special rotor bars topologies. The movement is taken into account by means of the moving band technique, the Maxwell stress tensor, and the mechanical oscillation equation. The model is applied to a brushless doubly fed induction motor.

This work uses a method based on the two-dimensional (2-D) finite-element method (FEM) and on the circuits theory to model the interbar currents in a skewed cage induction motor. With this model, the effects of the stator-slot opening on interbar currents are analyzed. Two values of the stator-slot width are considered. The skewing effect is taken into account by the multislice technique.

A methodology allowing one to include iron losses in voltage fed time stepping finite elements simulations is presented in this paper. Hysteresis, eddy currents and anomalous losses models are introduced in the 2D field formulation based on the magnetic vector potential. The influence of the losses on the behavior of an Epstein frame is given. Comparison between simulated and measured results shows the validity of the proposed methodology.

This paper deals with the coupling between magnetic forces, forced vibrations and noise in a Switched Reluctance motor. The finite element method is used to obtain the magnetic forces and forced vibrations. The boundary element method is used for acoustic computations.

This work presents an improved method to take into account the magnetic nonlinearity in time-stepped two dimensional finite element calculations. A differential magnetic reluctivity tensor is employed. Also, in order to model the nonlinearity, a Langevin function is used. Numerical convergence is faster than classical procedures.

In this paper, a finite element model is used to investigate the squirrel cage induction motor vibrational behavior. This model allows to calculate the winding and bar currents, the magnetic forces and motor structure dynamic response. The vibrations and magnetic forces are obtained by numerical calculations and validated by measurements.

This paper presents the implementation of the control loop in the simulation of the association converter/electromagnetic structure represented by two-dimensional finite element method. The state variable equations of the converter are constructed entirely in an automatic manner. These equations are then coupled to the electromagnetic structure equations, and finally solved simultaneously using time stepping procedure. In order to validate the proposed method, a simulation of an inverter connected to an electromagnetic structure including an hysteresis current control scheme is performed.

Numerical and experimental procedures are presented in this work in order to study the vibration behavior of switched reluctance motors (SRM). Experimental modal analysis and finite element methods (FEM) are used to determine the mode shapes and natural frequencies of the motor mechanical structure. The forces acting on the stator are evaluated by means of a local force density method. The results show that a 2D model is sufficient for analyzing mechanical vibrations in SRM created by electromagnetic phenomena.

International audience; The optimal design of a set of two permanent magnet generators that share the same cross section to reduce the manufacturing cost is presented using a gradient optimization algorithm. The optimization tool is used to define the optimal number of pole pairs of the set of machines and the optimal permanent magnets width respecting the geometrical and performance constraints. The design is validated using a FEM analysis tool.

A newly designed linear actuator using permanent magnets is analyzed. In order to evaluate its dynamic performance, the coupling between electromagnetic equations is established. Due to the different phenomena involved, analytical procedures cannot provide reliable results. Thus the magnetic forces and other quantities are obtained by 2D and 3D calculations. In order to obtain the 3D field values, edge elements are used; with this type of finite elements, modeling taking into account the permanent magnets is also introduced.

International audience; A method to model the switched reluctance motor is presented in this paper. The methodology is based on the simultaneous solution of the magnetic field, represented by the two dimensional Finite Element Method, with electrical circuit equations. With this model the currents in the windings are calculated and the force distribution on the stator teeth is obtained. The mechanical response to magnetic forces is calculated by a Finite Element code

This work uses a methodology based on 2D-Finite Element Method (FEM) and on the Circuits Theory (Independent Currents Method) to analyze the inter-bar currents on the rotor of cage induction motors. The Multi-Slice Technique is used to consider the skewing effect. Three conditions are considered: one inter-bar resistance, two inter-bar resistances and three inter-bar resistances. The results show the distribution of currents in the rotor bars, short-circuit rings and transversal resistances at a given time. The fundamental component of the inter-bar and surrounding bar currents are shown to help understanding the phenomenon. Este trabalho usa uma metodologia baseada no Método de Elementos Finitos 2D (FEM) e na Teoria de Circuitos (Método das Correntes Independentes) para analizar as correntes inter-barras no rotor de um motor de indução com rotor de gaiola. A Técnica de Multiplas Fatias é usada para considerar o efeito da inclinação das barras do rotor. Três condições são consideradas: uma resistência inter-barra, duas resistências inter-barras e três resistências inter-barras. Os resultados mostram a distribuição das correntes nas barras do rotor, anéis de curto-circuito e resistências transversais em dado momento de tempo. A componente fundamental da corrente nas resistências inter-barras e nas barras circundantes é mostrada para auxiliar na compreensão do fenômeno.

In this paper, the finite elements method capabilities are used to calculate the magnetic origin forced vibrations of a switched reluctance motor, taking into account the measured viscous damping. The forced vibrations calculations are validated by measurements.

The single-phase line-start permanent magnet synchronous motor is studied in this paper as an alternative for the single-phase induction motor used in appliances to obtain gain in efficiency. The two dimensional finite element method is used to represent the machine. The motor is fed by means of an electrical circuit and the analysis is carried out through the simultaneous solution of the electrical feeding circuit equations and the field equations. >

Numerical and experimental procedures are presented in this work to analyze the vibratory behavior of squirrel-cage induction motors. Experimental modal analysis and rotational experiments are employed to determine the modal parameters and vibrations of the motor mechanical structure, respectively. The forces acting on the stator are evaluated by means of a local force density method. Finally an identification study of the main vibrations spectrum components is made.

The influence of the current switching angles on the vibrational behavior of switched reluctance motors (SRM) is presented in this paper. It is possible to obtain lower vibrational levels for a given speed and load, if the switching angles of the converter feeding the motor are adequately changed. A complete numerical model is presented in this paper, which allows the investigation of the mechanical behavior of SRM. This model comprises the SRM windings currents calculation, the evaluation of the magnetic forces in the machine structure and the mechanical dynamic response of the SRM structure.

This work uses a methodology based on 2D-finite element method (FEM) and on circuit theory (independent currents method) to analyze the inter-bar currents on the rotor of cage induction motors. The multislice technique is used to consider the skewing effect. Three conditions are considered: one inter-bar resistance; two inter-bar resistances; and three inter-bar resistances. The results show the distribution of currents in the rotor bars, short-circuit rings and transversal resistances at a given time. The fundamental component of the inter-bar and surrounding bar currents are shown to help understand the phenomenon.

This work uses a methodology based on the two-dimensional finite-element method and on the circuits theory (independent currents method) to calculate the inter-bar currents and analyze their effect on the performance of the polyphase cage-induction motors. The circuit theory is used to couple the rotor circuit equations to the field equations. The multi-slice technique is used to consider the skew effect.

In this work a method of study for electrical machines (permanent magnet synchronous motors) fed by static converters is presented. The electrical machine is represented by a finite element model. A step by step process with respect to time is used to solve the coupled problem: electrical machine and external electrical circuit. Calculation and experimental results are presented so as to validate the simulation procedures. >

A method allowing coupling of static converters with electromagnetic devices represented by finite elements analysis is presented. Special attention is paid to the fact that the state-variable equations of the static converter are calculated automatically. These equations are then solved simultaneously with those of the electromagnetic structure, step by step with respect to time.