bluuebunny/crossref_metadata_2025_split huggingface dataset:
Parameter Estimation, Condition Monitoring, and Diagnosis of Electrical Machines
Authors: Vas Peter 
Published: November 2023

Abstract
Condition monitoring of electrical machines and drive systems is a vital factor to achieve efficient and profitable operation of a large variety of industrial processes. Similarly, parameter estimation is important for the machine designer, and invaluable to the operator of modern drives implementing various types of controllers. It is also necessary to know the machine parameters for a number of simulation purposes. The chapters in this volume cover recent trends and advances in these and other areas, including sections on on-line and off-line parameter estimation of smooth-air-gap and salient-pole electrical machines, their diagnosis, and condition monitoring. New real-time monitoring devices, vibroacoustic techniques, and the symptoms and possible causes of failures of electrical machines are also discussed. In the book a unified and in-depth physical and mathematical analysis of the various parameter estimators and condition monitoring methods is presented. For this purpose, where possible, space phasor theory is utilized and the most recent and modern developments in the field are incorporated. The book is intended for academic and professional electrical engineers, and all those responsible for the performance, maintenance, and design of electrical machines and drive systems.
Introduction
Authors: Vas Peter 
Published: November 2023

Abstract
In this book, the on-line and off-line parameter estimation of smooth-air-gap and salient-pole electrical machines, and their diagnosis and condition monitoring are discussed. Great emphasis is laid on presenting an unified and detailed physical and mathematical description of the various parameter estimators and condition-monitoring techniques. For this purpose, where possible, space phasor theory is utilized and the most up-to-date and modern developments are incorporated. Parameter estimation is extremely important for the machine designer, but it is also invaluable for the operator of modern drives implementing various types of controllers. It is also necessary to know the machine parameters for various simulation purposes. Furthermore, changes in certain machine parameters can also indicate the existence of certain types of malfunctions. Conventional techniques for determining machine parameters sometimes have the drawback that they are based on a number of assumptions that are not valid under all operating conditions.
Monitoring Various Machine Parameters
Authors: Vas Peter 
Published: November 2023

Abstract
In this chapter, conventional techniques will first be described, which can be used for the measurement of various parameters of electrical machines. This is followed by presenting some other, alternative, techniques. In this section, two tests are described which are suitable to obtain the electrical parameters of symmetrical three-phase induction machines and single-phase induction machines. These are the locked rotor test and the no-load test. By the application of these tests, it is possible to determine the parameters which are present in the steady-state equivalent circuit of an induction machine.
Spiral vector analysis of the induction motor
Authors: Yamamura Sakae 
Published: November 2023

Abstract
Figure 3.1 shows a model for the induction motor analyses in this book. A three-phase induction motor is presented, and, unless otherwise specified, this is the motor assumed throughout this book. On the primary or stator side there are three phase windings, and on the secondary or rotor side there are also three phase windings. Although they are drawn as concentrated windings, their coils are inserted into slots pheripherally distributed on the cylindrical surface of the stator and rotor. When each phase winding is the same in structure and when the three phase windings are symmetrically positioned in space, the motor is called a symmetrical motor. The following analyses will treat only those symmetrical machines for which the three phase windings have the same circuit constants.
Transformation of transient-state equivalent circuits of the induction motor
Authors: Yamamura Sakae 
Published: November 2023

Abstract
In Section 3.5, the steady-state equivalent circuit of the induction motor was transformed to derive T-I and T-II type equivalent circuits from T type equivalent circuit. Although they have the same input-terminal impedance, FAM control derived different features from the different equivalent circuits. The same variable transformation will now be applied to T type transient state equivalent circuit to derive T-I and T-II type transient-state equivalent circuits.
Analysis and control of the synchronous motor as a control motor
Authors: Yamamura Sakae 
Published: November 2023

Abstract
The synchronous motor has been used for many years as a constant speed motor. Owing to remarkable advancements in inverter technique, inverter output voltage, current, and frequency can now be controlled very easily and quickly, and thus the synchronous motor is now used more and more as a fast response servomotor. In fast response applications, torque is the control output of the motor, as it was for the induction motor in the preceding chapters. As fast response motors, synchronous motors are now replacing DC motors, driving robots and numerically controlled machine tools, etc. These synchronous motors are rather small, usually less than several tens of kilowatts. However, the analytical theory is common to both small and large motors. The following analysis and control theory are applicable, irrespective of motor size.
Comparison of the induction motor and the synchronous motor as control motors
Authors: Yamamura Sakae 
Published: November 2023

Abstract
In modern motor control, control output is motor torque. By controlling the motor torque, state variables of driven equipment, such as speed, position, etc., are controlled to obtain their desired values. What is fed back in the control loop is speed, position, etc. The driving motor is located in the forward path and is under open-loop control. In the analysis of closed-loop control, which includes a driving motor in the forward path, the motor must be represented by its transfer function. Nevertheless, in many technical papers, AC motor control is treated as motor speed control. The reason for this is that electromagnetic transient phenomena have not been sufficiently analysed and it was thought that electromagnetic transients were inseparable from motor speed. In this book, it has been shown that they can be treated separately by FAM control. Thus, transfer functions have been obtained.
AC power supply for motor control
Authors: Yamamura Sakae 
Published: November 2023

Abstract
AC motor control is making rapid progress, mainly due to the advances in AC power supply. Formerly it was not easy to control AC voltage and current as vector quantities. In AC power supplies called variable-voltage constant-frequency (VVCF) or variable-voltage variable-frequency (VVVF), only one or two AC quantities are controlled. The control was a scalar control, and its application was mostly limited to AC motor speed control. Advancement of the semiconductor inverter has made it possible to control variables of the AC power supply as vector quantities. As a result, AC motor control has made remarkable progress. In the preceding chapters, the analysis and control theories of AC motors, which had been considerably lacking, have been treated and supplemented. Now AC power supply will be explained.
Linear Induction Drives
Authors: Gieras Jacek F 
Published: November 2023

Abstract
This work gives a complete review of linear induction drives. Particular emphasis is given to their design, construction, and practical application. Both state-of-the-art computer aided design methods and practical estimation methods for main dimensions and performance calculations are presented so that engineers can both generate accurate designs and test their preliminary ideas. Other practical problems discussed include those relating to variable-speed linear drives, power conditioning, and control methods. Testing techniques are also outlined. This book is addressed to practical electrical engineers involved in the design and construction of linear induction drives. It will also be valuable to mechanical engineers, who use the drives in other machines (e.g. machine took industry) and to graduate level students of electrical machine engineering.
Flat and Tubular Motors
Authors: Gieras Jacek F 
Published: November 2023

Abstract
In general, the secondary of a LIM can be composed of many parallel layers. Fig. 3.1 shows a flat, single-sided LIM with a multi-layer secondary consisting of i = k isotropic layers. The two-dimensional electromagnetic field for any conductive layer is described by eqn (3.25) and for any nonconductive layer by eqn (3.24). The general solutions for these equations have the form of eqns (3.32) and (3.33). The field distribution in the first layer i = 1 (air half-space) meets condition (3.52). The electromagnetic field equations for an induction machine with a multi-layer secondary are solved in publications by the author. On the basis of the electromagnetic field theory, the impedance of a multi-layer secondary and the impedances of each layer are derived in a paper by the author.
Design
Authors: Gieras Jacek F 
Published: November 2023

Abstract
The design of a single-sided LIM, similar to the design of any other electrical machine, is regarded as a problem of synthesis. This means that the operation Y = AX should be performed, where A is the mathematical operator of model being considered, X is the set of input data, and Y is the set of output results. Both sets, X and Y, can consist of a few subsets. The general design data of a single-sided LIM are: (i) geometry (longitudinal or transverse magnetic flux); (ii) type of primary winding (distributed or concentrated, single-layer, or double-layer); (iii) type of reaction rail (cage, solid ferromagnetic, double-layer, or multi-layer); (iv) thrust Fx at a given input frequency f, and linear velocity v; (v) input frequency f; (vi) linear velocity v; (vii) input voltage V1, and connection of the primary winding (Y or Δ.); (viii) duty cycle (continuous, short time, or short-time intermittent); (ix) class of insulation (For H). Instead of the linear velocity v corresponding to Fx, the synchronous linear velocity V8 is sometimes given.
Experimental Tests
Authors: Gieras Jacek F 
Published: November 2023

Abstract
Experimental tests play a very important part in the research and design of linear electric drives. Since errors in calculation are always possible, the parameters must often be indentified on physical models in order to verify the accuracy of calculations. A digital simulation of an electromechanical system also requires knowledge of its parameters which should when possible, be measured on the same or similar real system. The successful design of a new linear drive is nearly always accompanied by prior experimental tests performed on a physical model.
Introduction
Authors: Krawczyk Andrzej , Tegopoulos John A 
Published: November 2023

Abstract
Eddy currents have long been of interest to electrical engineers, and have been distinguished as a separate entity in the field of electromagnetism since Foucault1 first discovered their nature. Indeed, no one who deals with electrical engineering, either theoretically or practically, can be dispassionate about eddy currents. This results from their dichotomical nature, that is, they can be either desired or undesired. In one field of applied electricity they are consciously generated, and in others they are injurious and should be avoided or reduced. In fact, eddy currents are one of the main problems encountered in designing electrical apparatus, and for this reason we have focused our attention on this narrow topic. Leaving aside all the general electromagnetics books which tend not to describe eddy currents in detail, or those books which are not accessible to a wide readership because they are not published in English, there are three books dealing with eddy currents per se up to now (Lameraner and Stafl 1968; Stoll 1974; Tegopoulos and Kriezis 1985). One should mention here the book by Bunet (1933) but this describes only the phenomenology of eddy currents, so that it is useless from a computational point of view. The book by Tegopoulos and Kriezis is concerned with analytical methods applied mainly to two-dimensional configurations. The book by Stoll 1974 is concerned with both analytical and numerical methods, giving a wide spectrum of eddy current considerations. From the point of view of the numerical approach the finite difference method has been widely documented there. The book by Lammeraner and Stafl is devoted to the analytical approach only and covers one-dimensional configurations, so that its usefulness is limited.
Eddy currents due to motion
Authors: Krawczyk Andrzej , Tegopoulos John A 
Published: November 2023

Abstract
Relative motion of magnetic or non-magnetic structures carrying currents gives rise to the production of eddy currents which are either desirable or create losses, and are hence unwanted. In most real devices of this type two main parts can be distinguished: A stationary part, usually providing the excitation by electromagnets such as the stator of rotating or linear electrical machines, launchers, pumps, etc. In the magnetic circuits of these parts eddy currents are undesirable as they diminish the effectiveness of the device.
Pre- and postprocessing
Authors: Krawczyk Andrzej , Tegopoulos John A 
Published: November 2023

Abstract
As the creation of a continuous model without numerical results is only of theoretical value, the numerical methods are of little usefulness if not accompanied by systems which enable data to be introduced so as to obtain the technically important information after the numerical procedure is finished. These systems are commonly recognised as pre- and postprocessing systems. The question arises if the user of computer software is interested in pre- and processing procedures. Since the real engineering problems are so specific, it would be difficult to have a generalized ‘input-output’ analysis. Thus, one can say that commercial packages, although prepared in a ‘userfriendly’ manner, should provide the possibility of the user’s intervention at the initial and final step. This is the case in the analysis of eddy currents. Indeed, creating a mesh as well as getting appropriate results require some experience of the problem encountered. In the following sections the problems connected with pre- and postprocessing systems are pointed out only since they really constitute a subject by themselves and lie beyond the scope of this book.
Numerical methods for boundary-value problems
Authors: Neittaanmäki P , Rudnicki M , Savini A 
Published: November 2023

Abstract
There are many approximate methods for the solution of boundary-value problems, such as the finite-difference method, the weighted-residual method, the Rayleigh-Ritz method, the Galerkin method and the finite-element method. The primary difference between the finite-element method and most of other methods is that in. the finite-element method the approximation is confined to relatively small subdomains. It is, in a way, the localized version of the Rayleigh-Ritz method. Instead of finding an admissible function satisfying the boundary conditions for the entire domain, which, particularly for irregular domains, is often difficult, in the finite-element methods the admissible functions are defined over element domains with a simple geometry and no attention is paid to complications at the boundaries. This is one of the reasons that the finite-element method has gained superiority over the other approximate methods.
Unconstrained optimization
Authors: Neittaanmäki P , Rudnicki M , Savini A 
Published: November 2023

Abstract
As can be seen, the higher-order derivatives of a quadratic function are all zero. From a Taylor expansion (the first three terms are always exact) it follows that all functions with continuous second derivatives behave much the same as quadratic functions provided the region is small enough. This fact is essential for many optimization algorithms which minimize a quadratic function in a finite number of steps.
Linear least-squares
Authors: Neittaanmäki P , Rudnicki M , Savini A 
Published: November 2023

Abstract
This chapter is concerned with the least-squares solution of overdetermined systems of equations. We show how to convert the original problem into an equivalent, easier-to-solve problem using singular-value decomposition (SVD). There are methods which require less computer time and storage but they also deal less effectively with rank-deficiency, data errors and roundoff errors. Moreover, the proper use of SVD requires the specification of a threshold value which represents the accuracy of the original data and of the floating-point arithmetic as well. The SVD method is strictly related to the regularization approach. In practical solutions to ill-posed (ill-conditioned) problems the smallest non-negligible singular value and the regularization parameter have much the same meaning. Furthermore, linear least-squares subproblems arise quite often from nonlinear least-squares problems.
Numerical methods in electromagnetism
Authors: Neittaanmäki P , Rudnicki M , Savini A 
Published: November 2023

Abstract
In this chapter we apply the finite-element method to the models introduced in the previous chapter. The finite-element method introduced in Chapter 3 can be applied to approximate the solution of potential equations in electricity and magnetism. If the approximation for the scalar or vector potential is of order k then it is one order less for the field intensity associated with the potential. For example, if one applies linear elements to approximate the solution of the potential, the approximation is only piece-wise constant for magnetic and electric fields. Therefore it is necessary to develop approximation methods which are applicable directly to important physical quantities. Here, we introduce the least-squares principle for the static case (see Chapter 8). For other cases we shall utilize the potential formulation and apply a standard finite-element approximation in space and a finite-difference method in time.
Synthesis of sources
Authors: Neittaanmäki P , Rudnicki M , Savini A 
Published: November 2023

Abstract
This class of problems implies the determination of the position and/or the value of the source of the field in order to have a prescribed potential or field intensity in a controlled part of a field region. To synthesize a magnetic field with the required distribution one can use suitably arranged coils. A number of synthesis problems can be formulated. In particular, a magnetic field can be synthesized at a plane perpendicular to the axis of a solenoid.
Optimal shape synthesis
Authors: Neittaanmäki P , Rudnicki M , Savini A 
Published: November 2023

Abstract
The selection of the optimal shape of devices in order to fulfil given prescriptions and/or to save costs, subject to various manufacturing and operational limitations and constraints, is a basic problem in all disciplines of engineering (Haslinger and Neittaanmiiki [1988]). Throughout the last 30 years such problems have attracted remarkable attention in structural mechanics and especially in aeronautics; it was within the context of structural design optimization that, in 1960, the coupling was first proposed of finite-element analysis with mathematical programming methods. However, in spite of the intensive research carried out since then, optimal shape synthesis has not yet fully affected industrial applications, so that automated optimal design is still a rather imprecise subject.
Remarks on inverse and design problems
Authors: Neittaanmäki P , Rudnicki M , Savini A 
Published: November 2023

Abstract
Inverse problems and, more specifically, optimal design problems are no longer just a matter of abstract investigation by pure scientists interested in the solution of idealized problems; thanks to the present large, high-speed computers associated with modern numerical methods, they are increasingly going to attract the attention of engineers interested in the solution of real-life problems. The authors are convinced that, after a few decades impressively marked by the development of analysis tools, most future work in electromagnetics will be devoted to the finding of tools for the synthesis of fields. Yet a great deal of experience and effort by both mathematicians and engineers is needed before friendly, reliable and possibly generalpurpose methodologies are developed which are suitable for engineering applications. Anyway, the new era has already started; evidence of this can be found in the extensive and rapidly growing literature which has already been published on the subject. Unfortunately, this is scattered in a number of different journals, ranging from purely theoretical journals to those which are absolutely oriented towards applications. This is largely due to the broad multidisciplinary aspect of the subject, which is very stimulating, but, at the same time, necessitates the creation of new working groups and new occasions for meetings. No specific significant conference on inverse problems and optimal design in electromagnetism, for example, has been organized so far.
Introduction
Authors: Neittaanmäki P , Rudnicki M , Savini A 
Published: November 2023

Abstract
Since the finite-element method plays the central part in almost all our considerations, Chapter 22 provides readers with implementations of the finite-element method for elliptic boundary-value problems, including the nonlinear case. Discussion is limited to m-noded isoparametric Lagrangian elements. We give pseudocodes for the computation of local stiffness matrices and vectors and for the finite-element solution of a potential problem including a nonlinear finite-element-method solver based on the quasiNewton method.
Implementation of the finite-element method
Authors: Neittaanmäki P , Rudnicki M , Savini A 
Published: November 2023

Abstract
Most commercial finite-element packages are based on the isoparametric Lagrangian finite-element technique. The idea behind this technique is to transform all integrals into a reference element (triangle, square). The transformation from the reference element to a general, element is made using the finite-element basis functions. In what follows we concentrate on the two-dimensional case. Three-dimensional problems can be handled in the same way. For further details, see the book by Hinton and Owen [1977].