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The paper deals with the method of the stray losses calculation in single‐sided linear induction motors. The stray losses produced by the higher space harmonics of the primary winding MMF and by the primary slots have been discussed.

The transient performance of permanent magnet dc commutator motors has been simulated using a two dimensional finite element model. The simulations of start‐up characteristics and braking conditions are concentrated on. The finite element approach in simulating transients of dc motors is discussed with a proposed solution to the problem A finite element solution that ignores the induced eddy current losses in the small volume rotor is shown as a quick solution that gives fair accuracy. The results are compared against experimental data obtained for a 370 W permanent magnet dc motor using a data acquisition system.

The increased use of permanent magnet synchronous motors in small to medium power applications has made it imperative that these motors' performance can be modelled successfully. The accuracy of calculating the synchronous reactances determines the success of the modelling technique. An analytical method and the finite element method are used to calculate the synchronous reactances of two prototype synchronous motors. The calculations are compared with measurement for both motors. The results show that the finite element method is more reliable in obtaining synchronous reactances than the analytical method for rotor designs that are very intricate, although both methods show reasonable accuracy.

Discusses the 27 papers in ISEF 1999 Proceedings on the subject of electromagnetisms. States the groups of papers cover such subjects within the discipline as: induction machines; reluctance motors; PM motors; transformers and reactors; and special problems and applications. Debates all of these in great detail and itemizes each with greater in‐depth discussion of the various technical applications and areas. Concludes that the recommendations made should be adhered to.

Introduces papers from this area of expertise from the ISEF 1999 Proceedings. States the goal herein is one of identifying devices or systems able to provide prescribed performance. Notes that 18 papers from the Symposium are grouped in the area of automated optimal design. Describes the main challenges that condition computational electromagnetism’s future development. Concludes by itemizing the range of applications from small activators to optimization of induction heating systems in this third chapter.

The purpose of this paper is to study the electric vehicle (EV) drive efficiency of a traction motor considering regenerative braking according to various motor cores.

A software program was developed to predict the driving performance of an EV. It determines the driving mileage, the required power of the traction motor, and the operation points on a torque-speed map when drive cycles are given. The driving performance is calculated from the battery capacity, vehicle specification, and efficiency map of the traction motor computed using the finite element analysis.

As a result, the motor core is a significant design variable for raising the driving mileage of an EV. It is noted that the change of electrical steels used for the motor core is the lowest priced method of increasing the driving range by 2 km.

The comparative analysis of motor core by replacing 35PN250 to 25PNX1250F results in improvement effects traveling 4.62 and 5.16 km farther in the Simplified Federal Urban Driving Schedule (SFUDS) and Highway Fuel Economy Driving Schedule (HWFET), respectively. It was also verified that regenerative braking system is able to enhance drive efficiency by 29-31.3 km in the SFUDS and 6.5-7.3 km in the HWFET. From comparison of price rise for increasing driving mileage by 2 km, it is noted that the change of electrical steels used for the motor core is the lowest priced method.

The aim of the paper is to find the simple and accurate model for the analysis of a drive with a tubular linear permanent magnet machine (TLPMM). Attention is paid to the models that take into account the saturation effects and is useful in the calculations of electromagnetic forces.

A circuit model and a field‐circuit model (FCM) are considered. The FCM includes finite element (FE) formulation for the axisymmetric electromagnetic field, equations which define the connections of windings and converter elements, and expressions that describe the control system. The FE method is used to determine the parameters of the circuit model. In order to simplify the circuit model, saturation effects caused by armature reaction are ignored. The electromagnetic force calculation is based on the virtual work principle and uses an approximate expression for the derivative of system co‐energy. The results obtained for the proposed models have been compared.

The proposed FE method of force calculation conforms with the applied method of movement simulation. For the rotor position when the cogging force is equal to zero the calculated cogging force is “almost” zero within seven‐decimal‐place accuracy. The effects of armature reaction on the performance of a TLPMM machine are similar to those which occur in a classical DC machine; in particular the demagnetising effect caused by saturation is observed.

The paper shows the influence of the saturation effects on the electromagnetic force of a TLPMM. In the case of “strong saturation”, the classical circuit model may be inappropriate for engineering calculations.

This paper aims to investigate three low-evaluation-budget optimization techniques: output space mapping (OSM), manifold mapping (MM) and Kriging-OSM. Kriging-OSM is an original approach having high-order mapping.

The electromagnetic device to be optimally sized is a five-phase linear induction motor, represented through two levels of modeling: coarse (Kriging model) and fine.The optimization comparison of the three techniques on the five-phase linear induction motor is discussed.

The optimization results show that the OSM takes more time and iteration to converge the optimal solution compared to MM and Kriging-OSM. This is mainly because of the poor quality of the initial Kriging model. In the case of a high-quality coarse model, the OSM technique would show its domination over the other two techniques. In the case of poor quality of coarse model, MM and Kriging-OSM techniques are more efficient to converge to the accurate optimum.

Kriging-OSM is an original approach having high-order mapping. An advantage of this new technique consists in its capability of providing a sufficiently accurate model for each objective and constraint function and makes the coarse model converge toward the fine model more effectively.

Design of small disc-type permanent magnet (PM) brushed DC motors for servomechanisms is challenging. The purpose of this paper is to propose a special coreless double-sided structure. This easy to manufacture motor has two set of shifted concentrated windings on both sides of the rotor. All of the coils in each winding are simply connected in series. A simple arcless commutator, which shares the features of both the usual commutators and slip rings, is connected to each winding at only two points.

By replacing the PMs with an equivalent current density, main design equations of the motor have been derived through the solving of scalar Poisson equation. A radial division technique has been used to take the radial variations into account. This provides the ability of considering various shapes of coils and PMs. A novel iterative algorithm has been proposed to design a motor with high torque capability, compared to other coreless counterparts. Some design variables are obtained based on an independent optimization problem, which maximizes the active portion of windings. The other variables are calculated in such a way that the design requirements are satisfied.

The feasibility and capability of the new structure have been proved by prototyping a sample motor. Comparing the design outputs with the results of the 3D finite element analysis and experimental tests shows a good agreement. This verifies the accuracy of the proposed design method.

A new structure for PM brushed DC motors and a novel algorithm for its design has been developed.

The purpose of this paper is to describe a new method for selective harmonic elimination in a two-level three-phase inverter-fed direct torque controlled (DTC) permanent magnet synchronous motor (PMSM) drive to suppress unwanted resonant frequencies.

The design methodology is based on random space vector pulse-width modulation (RSVPWM) of PMSM drives. MATLAB simulations support the validity of suggested structure.

The simulation results of the proposed algorithm exhibit the development of a proper gap at the selected frequency in the frequency spectra of the motor input currents and voltages as well as lowering the ripples in the PMSM electromagnetic torque, stator current and flux linkage responses in compared with traditional DTC.

The proposed algorithm is a revised form of the RSVPWM technique used in a closed-loop structure along with a sliding mode speed controller which is capable to deal with nonlinear motor loads in an online manner. This study can be beneficial for the designers of AC motor drive system who attempt to find a modulation method that can create a selective gap in the power spectrum density of the motor input voltages and currents, therefore, promote an acoustically pleasant drive or alleviate unwanted motor vibrations.