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This paper proposes an indirect method for the identification of moving vehicular parameters using the dynamic responses of the vehicle. The moving vehicle is modelled as 2-DOF system with 5 parameters and 4-DOF system with 12 parameters, respectively. Finite element method is used to establish the equation of the coupled bridge–vehicle system. The dynamic responses of the system are calculated by Newmark direct integration method. The parameter identification problem is transformed into an optimization problem by minimizing errors between the calculated dynamic responses of the moving vehicle and those of the simulated measured responses. Glowworm swarm optimization algorithm (GSO) is used to solve the objective function of the optimization problem. A local search method is introduced into the movement phase of GSO to enhance the accuracy and convergence rate of the algorithm. Several test cases are carried out to verify the efficiency of the proposed method and the results show that the vehicular parameters can be identified precisely with the present method and it is not sensitive to artificial measurement noise. [ABSTRACT FROM AUTHOR]

A multi-slice finite element model for wireless magnetic resonant energy transfer systems with circular spiral tape coils is presented. As the system is constructed using distributive capacitance, it is difficult to determine the parameters in the equivalent circuits analytically. To address the aforementioned problem, a multi-slice axisymmetric finite element method (FEM) is applied to analyze this wireless power transfer system. The merits of the proposed method are that three-dimensional FEM is not required and yet the distributive capacitances among the coils can be fully included in the proposed two-dimensional model. Compared with normal axisymmetric FEM without multi-slices, the proposed method can include the effect of distributive capacitance to produce more precise solutions. The proposed method is validated against experimental data. [ABSTRACT FROM AUTHOR]

A novel post-assembly magnetization method of direct-start interior permanent magnet synchronous motor is presented. The squirrel cages in the rotor are ingeniously used as exciting coils for the realization of magnetization. The advantage is that no special magnetizing fixtures are required. A finite-element method, which addresses dynamic material properties of the magnets and yet can be implemented readily in the software, is presented for finding the parameters of the magnetization circuit. A numerical computation is reported to validate the proposed method. [ABSTRACT FROM PUBLISHER]

A general and precise method to model rotary machines based on transient magnetic field computation using finite-element method (FEM) is presented. The merits of the proposed method are that the nonlinear iteration on the rotor position can be avoided. Formulas to predict the rotor position and speed of the machine are deduced based on Taylor's expansion. A curvilinear element is used on the two sides of the sliding surface to reduce the numerical noises arising from mesh rotation. The proposed methods for dealing with matching boundary conditions and periodic boundary conditions are very general, accurate and flexible. Typical numerical experiment shows that the numerical error of the local magnetic potentials on the motion sliding surface is only one twentieth of that of traditional interpolation method. [ABSTRACT FROM PUBLISHER]

A multi-stage diagonally-implicit Runge-Kutta (DIRK) algorithm is applied to discretize the time variable in transient magnetic field computation using finite element method (FEM). A formulation, which has the same format as the backward Euler (BE) algorithm for both linear and nonlinear problems, is deduced for simple and ready numerical implementation. The DIRK algorithm is compared with the BE algorithm which is an effective and popular algorithm in FEM. The merits and disadvantages of these two algorithms are highlighted. An ingeniously combined algorithm exploiting the merits of both BE and DIRK is presented and a numerical experiment shows that it can significantly improve the accuracy with no additional computing burden. For nonlinear problems, a DIRK nonlinear iteration strategy is presented and it can be shown that the total computing time of one integration time step can be shortened by about 36% without any accuracy loss in the solutions. [ABSTRACT FROM PUBLISHER]

Focuses on a study which presented a sub-block algorithm for the time stepping finite element solution of problems in which sets of electric machines are coupled together. Basic equations of induction motors; Example of the algorithm's application; Conclusion.

Presents information on a study which proposed a two-dimensional multislice time-stepping finite element method of skewed rotor induction motors to include the interbar currents in finite-element analysis. Field equation in the iron and air-gap domains; Field equation in the stator conductor domain; Maxwell's equations in the rotor conductor domain; Global system equations; Use of the Backward Euler's method; Comparison of computed and tested results; Conclusion.

A general and simple method to couple arbitrarily connected circuits and multislice magnetic fields in the time stepping finite element analysis of electromechanical devices and electrical machines is presented in detail. The merits of the proposed method are that the sparsity of the finite element equations is improved, the formulations to be described wilt allow unequal division of the axial length of the motor in the multi-slice model, the stranded windings (with negligible eddy current) and solid conductors (with eddy current) in the field domain can be connected arbitrarily with the external circuits, and the coefficient matrix of the system is symmetrical and the nonlinear power electronic elements can be easily maneuvered in the formulations. As illustrating examples, the proposed approach is used to simulate the operations of a brushless d.c. motor and a hard disk drive spindle motor. [ABSTRACT FROM AUTHOR]

Presents a study on a time stepping finite element model (FEM) for analyzing the performance of brushless direct current motors. Information on the circuit-field-torque couple FEM model; Application of the model; Conclusion.

The write field distribution for a perpendicular writer was investigated using finite-element (FE) analysis. The slanted write fields due to shield pieces at the trailing edge and the leading edge of the pole tip, and the side shields are analyzed. The analysis shows that the use of the shielded pole leads to a change in the saturation levels in the main pole tip, affecting the write field distribution. The effects of the side shield and other design parameters on the write field in cross-track direction are discussed. [ABSTRACT FROM AUTHOR]