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The paper deals with a voltage feeding algorithm for a linear induction drive that takes into account the end-effect and the actual distribution of the windings. It realises a decoupled control of the thrust and of the magnetising condition of the machine. In order to take into account the end effect, different space harmonics of the flux density distribution must be considered. For this reason a suitable state observer has been adopted. The considered observer is arranged as a diagonal system of linear differential equations, therefore it gives a fast evaluation of the estimated quantities. The reference currents computed according to the field oriented strategy, are used by the feeding algorithm in order to evaluate, at each sampling interval, the reference vector of the supply voltage. This vector is adequately modulated by means of the vector PWM.

The paper presents a further tool of software MADES (Machine Analysis DESign) oriented to no specialist operators in the field of design and analysis of linear induction machines (LIMs). In particular the presented version has been oriented to the analysis of a LIMs in one and two dimensional approach. The really advantage of this tool can be carried out especially in un-balanced feeding conditions and in absence of standard geometrical, electrical or magnetic symmetry.

In the paper a method, for the evaluation of the main electric and magnetic quantities in electrical machines, is proposed. This technique, approaches and solves any problem directly in the time domain.

A new antiskid strategy which maximizes the torque in adherence conditions during the braking phase and the braking time for railroad vehicles is proposed. This control strategy is based on the knowledge of different kinematic parameters of the whole system in real time and could be effectively implemented with the availability of a very fast microprocessor.

The paper revisits some mathematical models of induction linear motor by the point of view of the control purposes. The results of different mathematical models used for the analysis of a double side linear induction motor are compared. All the adopted procedures are formulated by means of space vector theory and take into account, with different simplificative hypotheses, the end - effects and the real distribution of the primary windings. The edge effects are always neglected. The aim is the analysis of the different methods in order to achieve a good compromise between a sufficient accuracy of the results and a fast response, necessary when the model is used in a real time control system. After a theoretic analysis of the adopted models a comparison among different formulations is developed and a set of simulations are presented and discussed.

In this paper, the performance of a vector control algorithm, applied to a linear induction motor (LIM), has been investigated. Specifically, the authors' interest is to verify the possibility to control, independently, the thrust and flux density of a LIM, by means of two MMF components and to test the sensitivity of response with respect to these quantities. >

The paper deals with an original design of an electromechanical actuator suitable for the fulfilment of an integrated system that is able to develop a contemporary motion both of rotation both of axial displacement. The traditional rotational movement, that is continuous, bases itself on a PM DC brushless design characterised by a sector structure with axial magnetisation. The axial motion can be developed by exploiting the original map of the magnetic flux density produced, in the air-gap, by the anisotropy and by magnets allocation. In this note a complete description of the actuator is presented together with the electromagnetic analysis suitable for design indications.

An investigation of PM motors by means of FEM analysis has led to suggestions concerning the good design of the homopolar motor as well as concerning the practical equivalence between the homopolar and the griffes solutions in terms of torque density. This result could be very important for the adoption of this machine in industrial or automotive applications where low-cost drives with PM DC motors are presented. A study of flux density field maps for two typical griffes configurations is carried out, and comparisons among the different solutions are presented. >

The paper deals with the analysis of an artificial neural network (ANN) approach suitable for online faults detection of induction machines. The aim of this paper is to develop an alternative with respect to traditional fault detector techniques that overcomes the limitations of present technology. After an analytical discussion about theoretical principles and relations used for the diagnosis of electrical machines failures, a simple ANN algorithm is presented and tested. The results prove the feasibility of to tool arranged by means of artificial neural network for a fast and accurate detection of stator faults in induction machines. Furthermore a good accuracy of the results have been achieved notwithstanding the great simplicity of the algorithm with respect to a complete model arranged by a space vector analysis. >