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This paper presents a novel approach for incorporating noncuboidal and rotated cuboidal sources of magnetic field in 3-D Fourier modeling. Based on the periodicity present in the geometry, a Fourier integral is applied in two directions. By changing the integration boundaries in the $y$ -direction to a linear function of the $x$ -direction, nonideally shaped magnetic field sources (i.e., coils and permanent magnets) are incorporated. From the electromagnetic example geometries analyzed in this paper, the magnetic field as derived with 3-D Fourier is over 99% accurate compared to 3-D finite-element models. [ABSTRACT FROM AUTHOR]

This paper develops a novel magnetomotive forces (mmfs) distribution model along the transverse direction for the 3-D analysis of linear induction motor, and it investigates the influence of a laterally asymmetric cap-secondary on the thrust, vertical force, lateral force, and efficiency in a prototype single-sided linear induction motor for linear metro. First, the mmf distribution model and its working conditions are defined, and the model is transferred into a mathematical model. Second, the air-gap flux and secondary eddy current in a prototype linear motor with a cap-secondary are obtained by a 3-D space harmonic analytical method. Third, the thrust, vertical force, lateral force, and efficiency of the test motor are analyzed with various lateral deflection, and the power factor in secondary is also presented. Finally, these results are experimentally verified by measurements on the test rig of the linear motor, and the comprehensive effect on the operating performance can be accurately calculated by the mmf model. [ABSTRACT FROM PUBLISHER]

This paper presents an analytical method for evaluating the magnetic flux density produced by spherical permanent magnet arrays used in spherical actuators. To investigate the performances of magnetic arrays, analytical models are used due to their lower computational time compared to 3-D finite element analysis. This paper presents an analytical model for the calculation of the magnetic field produced by a spherical permanent magnet array using magnetic charge modeling. To obtain the total magnetic field solution, first the magnetic field produced by a single spherical tile is considered. By means of superposition, the magnetic field produced by the array is obtained. Two magnet array topologies are modeled and the analytical results are validated using finite element analysis. [ABSTRACT FROM AUTHOR]

In this paper, a semi-analytical model is derived to calculate the magnetic flux density around a magnetic shield with finite dimensions. The proposed modeling is based on Fourier modeling, which is extended with mode-matching. The described model has less than 0.2(%) error with respect to finite element modeling for the given configuration. Furthermore, the paper shows that assuming a magnetic shield with infinite dimensions introduces a significant error with respect to a magnetic shield with finite dimensions. [ABSTRACT FROM AUTHOR]

In order to reduce the thrust ripple of linear servo system, a double-sided air core permanent magnet linear servo motor with trapezoidal shape permanent magnets (TDAPMLSM) is proposed in this paper. An analytical model of the motor for predicting the magnetic field in the air-gap at no-load is introduced. This model is derived based on the equivalent magnetization intensity method, and its accuracy is validated by using the results obtained from the finite-element method. The key dimensions that affect the air-gap magnetic field are analyzed based on the analytical model, and the design is optimized by using genetic algorithm. A thrust ripple reduction of 70.6% is achieved by optimization. The proposed analytical model may be used for a quick and reliable design and design optimization of the TDAPMLSM. [ABSTRACT FROM AUTHOR]

This paper presents a comparative analysis of the characteristics of high-speed permanent magnet synchronous machines (PMSMs) with diametrically magnetized rotors under different construction conditions of the rotor magnetic circuit. An analytical method is adopted to predict the magnetic field distribution and to calculate the electrical parameters by using the transfer relations based on a two-dimensional model in a polar coordinate system. In addition, three types of PMSMs with diametrically magnetized permanent magnets are proposed in this work. The electrical parameters are estimated and the magnetic field distribution is analyzed for those models, and these results are compared with those obtained using the finite element method; the two sets of results are found to be in good agreement. On the basis of the analysis results, a real model manufactured and the validity of our results is demonstrated by performing suitable experiments. [ABSTRACT FROM AUTHOR]

This paper considers analytical and numerical techniques to model the magnetic field distribution in a tubular actuator with skewed permanent magnets (PMs). A fast 3-D analytical model based on Fourier analysis is developed for calculation of the various field components resulting from the skewed PMs for various skewing topologies. This techniques provides means for validating the assumptions of 2.5-D multilayer methods. Furthermore, a 2.5-D analytical multilayer model is derived for calculation of the cogging force due to the slot openings including skewed PMs. The analytical methods are validated by means of 3-D finite element analysis. [ABSTRACT FROM PUBLISHER]

This paper presents an exact 2-D analytical model for predicting the armature reaction magnetic field in idealized structures of permanent-magnet tubular linear machines with surface-inset mounted magnets. The armature reaction magnetic field distributions is analytically derived and compared to finite-element analyses. The analytical solution allows the prediction of the machine inductance and reluctance force in closed forms, and facilitates the evaluation of any possible partial irreversible demagnetization of the magnets. It can also be used to estimate resistance limited eddy-current losses in armature windings and permanent magnets. The developed analytical model can be advantageously used for the analysis and design of a class of linear tubular machines. [ABSTRACT FROM PUBLISHER]