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In this chapter we will look at some basic drive implementations with a DC machine as discussed in section 10.5 starting at page 272. Our aim is to arrive at generic models of all major drive components, (excluding the DC machine which has already been discussed) which we can then transpose to a Simulink and/or Caspoc type environment in the tutorials at the end of this chapter. [ABSTRACT FROM AUTHOR]

The genesis of the ideas required to build an electrical machine can be traced back to the discovery of electromagnetism by the Danish scientist Oersted in 1819-20. Oersted discovered that a current in a wire could deflect a compass needle. Thus the connection between a current carrying conductor, a magnetic field and mechanical movement was established. A German chemist named Schweigger, who studied Oersted's experiment, found that if the wire carrying the current was wound into a coil then the deflection of the magnet was greatly increased. The Professor of Chemistry at Cambridge, Cumming, coined the term ‘Galvanometer' for this configuration and used it as a current detector. At around the same time Ampère developed a theory to support the observations made about current carrying coils of wire. In 1825 Sturgeon found that putting an iron core in the coil increased the magnetic field strength considerably for the same current. [ABSTRACT FROM AUTHOR]

This chapter considers an extension of the single phase transformer (ITF) model to a two-phase space vector based version. The introduction of a two phase (ITF) model is instructive as a tool for moving towards the so-called ‘ideal rotating transformer' ‘IRTF' concept, which forms the basis of machine models for this book. The reader is reminded of the fact that a two-phase model is a convenient method of representing three-phase systems as was discussed in section 4.6 on page 89. The development from ITF to a generalized two inductance model as discussed for the single phase model (see chapter 3) is almost identical for the two-phase model. Consequently, it is not instructive to repeat this process here. Instead, emphasis is placed in this chapter on the development of a two-phase space vector based ITF symbolic and generic model. [ABSTRACT FROM AUTHOR]

The induction machine is by far the most commonly used machine around the globe. Induction machines consume approximately one third of the energy used in industrialized countries. Consequently this type of machine has received considerable attention in terms of its design and handling. [ABSTRACT FROM AUTHOR]

The synchronous machine has traditionally been used for power generation purposes. For motor applications (when mains connected) its use is ideal when the operating speed must remain constant, i.e. independent of load changes. Starting up however needs special measures. [ABSTRACT FROM AUTHOR]

This chapter considers the basic working principles of the so-called ‘classical' set of machines. This set of machines represents the asynchronous (induction), synchronous, DC machines, and variable reluctance machines. The latter will be discussed in the book ‘Advanced Electrical Drives' currently under development by the authors of this book. Of these classical machines, the asynchronous machine is most widely used in a large range of applications. Note that the term ‘machine' is used here, which means that the unit is able to operate as a motor (converting electrical power into mechanical power) or as a generator (converting mechanical power into electrical power). The machine can be fed via a power electronic converter or connected directly to an AC or DC supply. [ABSTRACT FROM AUTHOR]

In this chapter the meaning of ‘real' and ‘reactive' power are explored for sinusoidal systems. Initially, single phase (so-called two wire) circuits are discussed as to gain an understanding of the energy flow within a circuit configuration that is representative for electrical machines. We will then extend this analysis to three-phase (three wire) circuits. In the final part of this chapter a set of tutorials is introduced to reinforce the concepts discussed. [ABSTRACT FROM AUTHOR]

The majority of electrical drive systems in use are powered by a so-called three-phase (three wire) supply. The main reason for this is that a more efficient energy transfer from supply to the load, such as a three-phase AC machine, is possible in comparison with a single (two wire) AC circuit. The load, being the machine acting as a motor, is formed by three phases. Each phase-winding of which has two terminals, yielding a total of six terminal-bolts, usually configured as sketched in figure 4.1. The phase impedances are assumed to be equal. [ABSTRACT FROM AUTHOR]

The aim of this chapter is to introduce the ‘ideal transformer' (ITF) concept. Initially, a single phase version is discussed which forms the basis for a transformer model. This model will then be extended to accommodate the socalled ‘magnetizing' inductance and ‘leakage' inductance. Furthermore, coil resistances will be added to complete the model. Finally, a reduced parameter model will be shown which is fundamental to machine models. As in the previous chapters, symbolic and generic models will be used to support the learning process and to assist the readers with the development of Simulink/Caspoc models in the tutorial session at the end of this chapter. [ABSTRACT FROM AUTHOR]

The simplest component utilising electro-magnetic interaction is the coil. The coil is a buffer component which stores energy in magnetic form. Aircored coils are frequently used (for example in loudspeaker filters), but coils with a core of (possibly gapped-) magnetic material are more common because of their increased inductance (or reduced size), which comes at the cost of reduced maximum field strength and increased non-linearity. [ABSTRACT FROM AUTHOR]

Electric motors are around us everywhere. Generators in power plants are connected to a three-phase power grid of alternating current (AC), pumps in your heating system, refrigerator and vacuum cleaner are connected to a single phase AC grid and switched on or off by means of a simple contactor. In cars a direct current (DC) battery is used to provide power to the starter motor, windshield wiper motors and other utilities. These motors run on direct current and in most cases they are activated by a relay switch without any control. [ABSTRACT FROM AUTHOR]