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Chapters 1–11 including the examples are appropriate for an introductory undergraduate course on energy conversion and renewable energy. The following examples in Chap. 12 encompass entire energy systems which include transformer, electric machine systems/drives, centralized (conventional) power system, distribution system analysis with/without power factor compensation, design of power plants...
In any negative feedback system the measured actual control variable xactual is compared with a given reference value xref. Ideally the actual instantaneous value of a control variable should follow the given reference value. However, this is not entirely possible and the quality of a control system depends to a large extent upon the type of controller used. In applications there are linear and nonlinear...
Single-phase systems are adequate for residential applications up to an apparent power S of 5 kVA (per residence), and 25 kVA single-phase pole transformers supply power to about 5–10 residences. In rural areas irrigation applications require single-phase motor ratings of up to 50 kVA. Above this rating three-phase power equipment must be employed for commercial and industrial applications.
Inductors discussed in Chap. 6 mostly have one winding only and a relatively large air gap to make it a linear device, where current and voltage are proportional to each other: if one defines in the time domain 7.1a $$ {{\hbox{v}}_{\rm{L}}}({\hbox{t}}) = {\hbox{L}}\frac{{{\text{d}}{{\text{i}}_{\rm{L}}}{\text{(t)}}}}{\hbox{dt}}, $$ then one can write in the phasor domain 7.1b $$ \tilde{\rm v}_{\rm{L}}(\hbox{t})...
For many electric motor drives constant angular velocity (ωm) and constant torque (Tm) operation is acceptable. Because of P = Tm⋅ωm the power delivered to the load will be constant as well. In many residential (e.g., air conditioner), commercial (e.g., elevator), and industrial (e.g., rolling mill, paper manufacturing) applications, the speed of drives must be variable and controllable from 0 to...
All components of the generic structure of the electromechanical drive system of Fig. 2.1 have been discussed, except the mechanical gear and the mechanical load. In this chapter the electrical torque T produced by the motor will be related to the mechanical load (L) torque TL and to the angular velocity ωm as transmitted to the mechanical load via the gear box. It is important to realize that the...
The rationale for this book is best characterized by a recent publication of the New IEEE-USA National Energy Policy Recommendation [1] stressing that the electric power system is an integral tool for the remaking of America. The clean and efficient production, transmission and use of electricity can play a key role in addressing the challenges of economic revitalization, climate change and “national...
The objective of this chapter is to analyze/present the different types and flux patterns of electric machines. These flux distributions are based on numerical solutions [1–5]. Moreover, to discuss the techniques and approximations involved in reducing the physical machine to a simple mathematical model and to give some simple concepts relating to the basic machine types.
The most common electric source of electrical energy is in the USA the public three-phase, 60 Hz [1–4] utility system. Within the continental US there are three distinct separate AC power pools: the Eastern, Western, and Texan system representing a total of 1,000 GW installed capacity. These separate systems are interconnected by relatively low power (100 MW) DC transmission lines in order to permit...
Static magnetic devices used in electromechanical energy conversion processes (e.g., rotating machines, rectifiers, inverters) are inductors and (permanent) magnets: their operation is based on Maxwell’s equations [1] and in particular for low-frequency (f < 50 kHz) applications on Ampere’s and Faraday’s laws neglecting displacement currents. Although the nonlinear characteristics of iron cores...
In Chap. 6 inductors have been analyzed. In these devices there are no moving parts. In this chapter the force ( $$ {\vec{\hbox{F}}} $$ ) and torque ( $$ {\vec{\hbox{T}}} $$ ) production in electromagnetic circuits such as magnets, actuators, relays, linear and rotating machines will be discussed. These devices have a stationary part (stator) and a moving part (rotor). Figures 9.1a, b illustrate...
The structure of an electromechanical drive system is given in Fig. 2.1. It consists of energy/power source, reference values for the quantities to be controlled, electronic controller, gating circuit for converter, electronic converter (e.g., rectifier, inverter, power electronic controller), current sensors (e.g., shunts, current transformer, Hall sensor), voltage sensors, (e.g., voltage dividers,...
Power Conversion of Renewable Energy Systems introduces conventional energy conversion components and systems, as well as those related to renewable energy which are important for a smart grid design. This volume covers systems first, and then in subsequent chapters describes the components of energy systems in detail. Readers will find examples of renewable and conventional energy and power systems,...
Since the beginning of railway electrification, power quality has been a main problem in railway networks because of their special characteristics. Many ways of power quality improvement have been investigated and applied to ac and dc traction systems through railway electrification history. This paper presents a perspective on power quality issues through railway electrification development and investigates...
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