bluuebunny/crossref_metadata_2025_split huggingface dataset:
Intelligent Control Power Electronic Systems
Authors: Dote Yasuhiko , Hoft Richard G 
Published: November 2023

Abstract
This book describes intelligent control and its use in power electronic systems, specifically AC motor drives and uninterruptable power supply (UPS) systems. The book covers both the fundamentals of the subject and its practical applications. From the Foreword by Lotfi A. Zadeh, Director of Berkeley Soft Computing Center, California: ‘What is unusual about [this book] is that it starts with a description of more or less classical control techniques; moves on to modern control and state space techniques; addresses in detail the complex issues arising in the analysis and design of robust control; takes up digital signal processing controllers; and finally, presents a very insightful exposition of soft computing techniques and their application to advanced control of AC drives and UPS systems.’
Vector control
Authors: Dote Yasuhiko , Hoft Richard G 
Published: November 2023

Abstract
The origin of vector control dates from the 1970s with the work of Professor Leonhard [1] and his student Blaschke [2]. An earlier dissertation described work of a similar nature by Hasse [3] who was a student of Professor Joetten at TH Darmstadt. Originally the approach was referred to as ‘field oriented control’. However, in this text the term vector control is used, which is presently the most popular term, particularly in Japan where the greatest numbers of commercial products using this control technique were first produced. The vector control concept had its roots in very early work by Blondel [4], Doherty and Nickle [5], Park [6], and Kron [7]. During most of the past 25 years much additional work has been done [8–-14] which has greatly expanded our knowledge of vector control throughout the world.
Finite Element Methods in Electrical Power Engineering
Authors: Reece A B J , Preston T W 
Published: November 2023

Abstract
This book is designed to give the theoretical foundation needed by the new user of finite elements in electrical power engineering, and shows how the equipment designer can benefit from finite element analysis. It is divided into three parts; theory, modelling,and application of the finite element method. The first part outlines relevant electromagnetics, including treatment of boundaries, saturation and permanent magnets. It also shows how the finite element equations can be formulated. The presentation throughout is aimed at giving the reader a physical understanding of the process. The second part deals with special aspects of finite element modelling of engineering problems, including problem formulation, data generation and post processing and emphasises the importance of engineering judgement. The final part is an assembly of 'real' magnetic and electric field problems solved by finite elements, including application to turbine generators, permanent magnet machines, switched reluctance drives, induction motors, transformers and bushings.
Formulation of electromagnetic equations in finite element terms
Authors: Reece A B J , Preston T W 
Published: November 2023

Abstract
As its name implies, the finite element scheme transforms a problem of complicated form in a continuous region into one in which the region is discretised and an approximate (though good) solution is obtained for the field quantity at the discretised points (the nodes). The nodes are linked to form elements of the selected shape. It will be evident that by suitable choice of element shape complicated geometries can be represented well, and that, in principle, each element can have different properties: with incorporation of suitable solution algorithms, the properties can be non-linear. Thus a large set of algebraic equations has to be derived, in a way to be described, to replace the governing partial differential equation.
Treatment of non-linear materials
Authors: Reece A B J , Preston T W 
Published: November 2023

Abstract
Soft magnetic materials are those for which the width of the magnetisation loop is small and remanence can, to a first approximation, be neglected. Examples are the electrical sheet steels. Hard magnetic materials are those with a wide loop, operating in the second (or even third) quadrant and hence behaving as permanent magnets.
Derived quantities
Authors: Reece A B J , Preston T W 
Published: November 2023

Abstract
A quantity frequently needed by designers is the total electromagnetic force (or torque) on an object (e.g. an actuator armature or machine stator /rotor). Less frequently there may be a need for the force distribution acting on a coil or surface so that stresses on a component or the electromagnetically induced vibrational and acoustic behaviour of a device may be evaluated. Calculation of electromagnetic forces and particularly force distributions raises serious philosophical arguments as discussed, for example, by Carpenter (1959) and Carter (1962). These aspects wi11, as far as possible, be avoided here.
Post-processing
Authors: Reece A B J , Preston T W 
Published: November 2023

Abstract
It may be thought that the purpose of post-processing is self-evident: deriving whatever extra information is needed over and above that provided directly by the solution (usually potentials, energy and with some programs, additional quantities requested in the control data). However, it is worth reviewing some purposes which may be overlooked in the rush to get useable numerical data.
Extensions for steady-state machine problems
Authors: Reece A B J , Preston T W 
Published: November 2023

Abstract
It will have been noted that the finite element equations are formulated in terms of applied scalar magnetic potentials or applied current densities. Thus when currents are known, the flux density distributions and flux linkages can be determined: in time-varying problems, the voltages induced in windings are also available. However, in the induction motor, for example, it is the applied voltage which is known, and the need is usually to compute the resulting currents and flux densities etc., for a given slip. With some approximations, discussed later, the rotor can be regarded as stationary, and slip dealt with by exciting the stator winding at slip fiequency, whilst calculating the induced voltage in the stator winding from the flux linkage and supply fiequency.
Time stepping for steady-state and transient problems
Authors: Reece A B J , Preston T W 
Published: November 2023

Abstract
The theory presented so far has dealt with magnetostatic conditions and cases where the excitation source (current or voltage) varies sinusoidally with time. It allows many problems to be tackled but there are deficiencies, even for steady-state cases. As pointed out in Section I 0.1, the assumption that voltage, current and field qmrntities all vary sinusoidally with time in a device with saturation implies that only a single value of permeability can be ascribed to each element, despite the variations of flux density throughout the time cycle. Additiona11y, second-order effects of motion are excluded.
Steady-state performance of large turbine generators: open circuit and load excitation and reactances
Authors: Reece A B J , Preston T W 
Published: November 2023

Abstract
Calculation of the open-circuit curve is, in principle, one of the simplest applications of the finite element method. There is no stator current and flux distributions and induced voltages can be calculated for the required range of field currents. In a large generator, three-dimensional effects are small and hence a two-dimensional model should give good results if approximate allowance is made for variations in the axial direction. As only fundamental frequency voltages are required, it is permissible to make calculations for a fixed rotor position relative to the stator slotting.
Turbine-generator transient parameters by simulated frequency response testing
Authors: Reece A B J , Preston T W 
Published: November 2023

Abstract
The Standstill Variable Frequency Injection Test which gives operational impedances as a function of stator frequency has been described in Section 10.4.1. A method of simulating this test using a two-dimensional finite element model has been outlined in Section 10.4.2 and the principles of modelling have been presented. The approximations necessary to allow a two-dimensional treatment and the question of rotor permeability are discussed there, as is the problem of discretisation appropriate to the wide frequency range of induced rotor current. This chapter takes the particular example of a 350 MW turbine generator and shows an approach which has been successful in predicting operational impedances and stator-field transfer functions. It compares calculated and test curves and briefly outlines how functional expressions can be derived for the impedances and hence how the various transient reactances and time constants may be derived.
Electric-field analysis in power transformers
Authors: Reece A B J , Preston T W 
Published: November 2023

Abstract
Chapter 20 gave examples of the use of the finite element method to determine the magnetic-field distribution in power transformers. However, magnetic design is only one aspect of the designer’s problem: a knowledge of the distribution and magnitude of the electric field is vitally important in producing a safe and economic design, and finite element analysis has an important role here. With transmission voltages up to 400 kV (r.m.s.) line and associated winding test voltages of 630 kV r.m.s. power frequency and 1425 kV pk lightning impulse the problems of configuring the high voltage (HV) winding, leads, stress control rings and bushings become apparent. On those rare occasions when something goes wrong, the consequences can be very serious. Figure 21. l indicates the severe damage that can be caused by a HV flashover, in this case between the corona shield at the coil end of the HV bushing and a neutral lead. The insulation on the lead has been severely ruptured under impulse test conditions and as a result a costly repair was needed.
Inverse Scattering Transform And N-Soliton Solutions
Authors: Hasegawa Akira , Kodama Yuji 
Published: November 2023

Abstract
In this chapter, we outline the method of inverse scattering transform (IST) for the nonlinear Schrodinger equation and its integrable higher order equation given in the form,
The term with c:/3, is the first integrable hierarchy of the NLS equation, and we call (4.0.1) the higher order nonlinear Schrodinger equation, the HNLS equation (Kodama 1985).
We then give the formula of the N-soliton solutions and their fundamental properties.
Before we discuss the IST method, we briefly summarize the well-known Fourier transform for solving the initial value problem of a linear equation. The reader will then find a similarity between these methods. In fact, the IST method is sometimes called the nonlinear Fourier transform.
Interaction Between Solitons In The Same Channel
Authors: Hasegawa Akira , Kodama Yuji 
Published: November 2023

Abstract
In order to increase the bit rate of a communication system, it is desirable to place solitons close to each other. However, because of the nonlinearity of the system, solitons mutually interact, leading to deterioration of the information-carrying capacity of the fibre. Chu and Desem (1983) showed that soliton interaction can lead to a significant reduction in the transmission rate by as much as tenfold. Blow and Doran (1983) showed that the inclusion of fibre loss leads to further increase of soliton interaction because of increased soliton width by the effect of loss. Georges and Favre (1991) also discussed an influence of amplifier noise-induced jitter on soliton interaction, and they found that the noise disturbs the soliton phase difference which modifies the soliton interaction.
Interaction Between Solitons In Different Channels
Authors: Hasegawa Akira , Kodama Yuji 
Published: November 2023

Abstract
In the previous chapter, we considered the interaction between solitons in the same channel where we assumed small (or zero) frequency differences between solitons, i.e. !AB! « 1 in (9.2.8). In this chapter, we first consider in Section 10.l interactions of solitons in different channels such as a case of the wavelength division multiplexing (WDM) with finite frequency separation. For an all-optical system, the WDM is well facilitated. However, in a soliton system with lumped amplifiers as discussed in Chapter 7, interaction of solitons between different channels may give rise to a change in frequencies of the solitons, and results in time displacements. This shift of soliton frequency is caused mainly in the following two processes.
Spatial Solitons, Stability, And Chaos
Authors: Hasegawa Akira , Kodama Yuji 
Published: November 2023

Abstract
The concept of an envelope soliton was originally initiated by the discovery of self-focusing phenomena in a dielectric fibre (Chiao et al. 1964). However the generation and transmission of optical solitons have been so successful that the soliton concept has become much more popular than self-focusing. As a result the stably self-focused light beams are now often called spatial solitons.
Dark Solitons
Authors: Hasegawa Akira , Kodama Yuji 
Published: November 2023

Abstract
In the wavelength range shorter than the zero group dispersion point where k!’ is positive, the soliton solution does not exist. However, even in this range of wavelengths, the portion without light, which is produced by chopping a continuous light wave, is known to form a soliton. Such a soliton solution is often called a dark soliton. Dark solitons also appear in space called spatial dark solitons. Spatial dark solitons have interesting applications in the switching and guiding of light beams. We present here. the theoretical and experimental properties of a dark soliton both in time and space.
Time-Domain Electrodynamics of Continuous Media
Authors: Shyartsburg A B 
Published: November 2023

Abstract
This chapter is devoted to nonstationary propagation of nonsinusoidal electromagnetic fields in media with plasma-like dispersion, such as solid and gaseous plasmas, ionic crystals, and waveguide systems. The parameters of these media, widely used in optoelectronics and radiophysics, are considered here to be time-independent, whereas the propagating electromagnetic fields may possess significant nonstationary distortions due to dispersion and absorption. Unlike the usual approach associated with Fourier expansions of travelling plane waves and parameters of the medium, we shall operate directly, with time-domain Maxwell equations.
Plane Algebraic Projective Invariants
Authors: Rothwell Charles A 
Published: November 2023

Abstract
This chapter provides a sufficient level of theoretical background material in projective geometry and algebraic invariant theory for the understanding of the planar algebraic invariant shape descriptions used in LEWIS!. Algebraic invariants are just one example of how indexing functions can be computed for real shapes and so this chapter paves the way for Chapter 4 to achieve its goal, namely to prove by experiment that indexing is one of the key steps to producing an efficient recognition algorithm.
Projective Invariants of Smooth Plane Curves: LEWIS2
Authors: Rothwell Charles A 
Published: November 2023

Abstract
Invariants can also be computed for planar objects that contain more general plane curves than lines and conics. The subsequent discussion develops a process for forming invariant signatures for a class of smooth plane curves. These signatures provide a projectively invariant shape description from which indexes can be computed. Consequently, the process can be used within the LEWIS invariant indexing architecture for recognizing planar objects with boundaries consisting of higher-degree curves than lines or conics. The actual recognition system discussed in this chapter is called LEWIS2, and although a different system from LEWIS1, it shares many common processes.
Invariants for 3D Objects
Authors: Rothwell Charles A 
Published: November 2023

Abstract
So far we have been able to demonstrate that index-based recognition systems can be built around invariant shape descriptors. The previous chapters have been dedicated to proving this. The LEWIS architecture has been used successfully to recognize two different object classes using either algebraic invariants or a canonical frame construction. In fact, as a result of building the systems we were able in the last chapter to formulate a list of criteria that all shape descriptors should possess. Nevertheless, it should be borne in mind that the object classes used in the systems so far are very limited; it has been demonstrated only that planar objects can be recognized reliably. There is a real concern that the scope of the available invariant descriptors should be broadened.
Echoes of Hope-Jones
Authors: Woodward Philip 
Published: November 2023

Abstract
Froment’s escapement looked simple enough to make if only I could lay hands on an electromagnet. It occurred to me that my electric razor might contain something of the kind and on taking it apart I found just what was needed. It worked perfectly from a low voltage battery with only one drawback - the noise made as the armature snapped hard up against the iron core of the magnet every two seconds. I thought of trying to cushion this with something soft, but any such expedient would make the stroke an uncertain quantity. This would be as bad as a variable force and would invalidate the whole scheme, so the noise would have to be tolerated. Erroneously, I persuaded myself that we would all get used to it, even to the point of missing it when it stopped.
Harrison and congreve
Authors: Woodward Philip 
Published: November 2023

Abstract
My two electrical clocks had used ratchet wheels to measure out the intervals of one minute between impulses. Could not such a system be used in an all-mechanical clock? In ignorance of horological history I thought this a novel concept, though Congreve had patented such a clock in 1808 and found it a home in Buckingham Palace. I shall return to Congreve later in the chapter. A far more significant figure was John Harrison, now chiefly remembered for his practical proof that timepieces could work accurately enough to solve the problem of finding the longitude at sea. My particular interest was in his socalled grasshopper escapement, which had been invented in about 1722. I wanted to learn all I could from this. If the idea underlying so smooth and silent an escapement could somehow be adapted to infrequent impulsing, I might succeed in making a clock with jumping minutes and no clicks. That was my aim.
Going without gears
Authors: Woodward Philip 
Published: November 2023

Abstract
In response to a few turns of the winding key once a week, the escape wheel of an ordinary mechanical clock has to make at least ten thousand turns. That ratio, about a thousand to one, could be achieved with a single gear mesh by using a wheel 20 feet in diameter engaging with a quarter inch pinion, though none but an eccentric designer of sculptural skeleton clocks would consider such a possibility. It never ceases to surprise me that the same ratio can be achieved in three meshes using gears only 2.5 inches in diameter with three of the same quarter inch pinions. It is of course the multiplicative property of gear ratios that makes a cascade of gears so effective, and there is the added advantage that intermediate arbors can be made to turn at the correct speeds for driving hour and minute hands. In a traditional regulator clock this is just what happens; the second, minute and hour hands are all on arbors of the power train.
The phase circle
Authors: Woodward Philip 
Published: November 2023

Abstract
It is of little consequence that the sinusoidal driving forces discussed in the previous chapter are never encountered in mechanical clockwork. Any repeating pattern of force applied to a simple high Q resonator at or near its resonant frequency looks to it like a sinusoid; it can hardly tell the difference, and reacts just as it would to a sinusoid. This little known fact makes the calculation of escapement error in practical situations relatively straightforward.
Aiming too high
Authors: Woodward Philip 
Published: November 2023

Abstract
In the end it was to prove fortunate that my first attempt at a free pendulum ended in failure, for otherwise I would not have been spurred on to make W5. W4 was a compact wall clock, about the size of a Vienna regulator, but with two pendulums of different lengths swinging side by side. The shorter pendulum, a half-second slave, operated a pair of count wheels and took impulse every fifteen seconds. The longer one was the master, which swung freely for four minutes before receiving an impulse, during which time it had made 173 full vibrations. I took some pleasure in choosing that prime number, but almost any other number would have done equally well, for if there is no contact with the free pendulum between impulses, it can hardly matter how many swings it has made. Nothing in the mechanism depends on the particular number, though it must of course be an integer. The bob could be raised to give 174 vibrations in the four minutes and work equally well without any other adjustment. When details of W4 were prematurely published (Woodward 1974), an unwise step in any branch of research, the irrelevance of the master pendulum’s frequency did indeed puzzle some readers, though not for long.
ws
Authors: Woodward Philip 
Published: November 2023

Abstract
The Shortt clock was a product of the electromechanical age, which preceded the electronic revolution by a century. In 1920 the pendulum still held sway, but the electromagnet offered possibilities of control undreamed of in pure mechanics. Without such stimulus, the Shortt clock would never have evolved. However, with the benefit of hindsight, it struck me as an interesting challenge to see what might have been possible without making any use of electricity at all. The Shortt clock uses electricity to rewind the remontoire escapements of its free pendulum and its slave, which are both mechanical tasks.
Clockwork with a difference
Authors: Woodward Philip 
Published: November 2023

Abstract
The 1860s saw the appearance of two most unusual regulator clocks, one in New England and one in Scotland. Both clocks were new to me until recently, both were eye-openers and I can think of no more pleasant way to finish this book than by giving a brief description of each. Their inventors were William Bond of Messrs Bond and Son, Boston, Massachusetts, and Lord Kelvin (then Sir William Thomson) of the University of Glasgow. By the merest chance, only three clocks of each type were made.