This book is of interest to electrical engineers, research engineers, professors, and students in theoretical or experimental physics. Above one million cycles, radiation resistance r 2 and external reactance x 2 preponderate, and as they are independent of the conductor material above one million cycles, the iron wire thus becomes nearly as good — or poor — a conductor as copper wire. The permanent values of current and e. With a bulk of condenser of 10 to 20 cu. In this case the constant potential-constant current trans- formation may be used to produce constant or approximately constant voltage at the load, by supplying constant current to the line; that is, the transmission line is made a quarter-wave length by modifying its constants, or choosing the proper fre- quency, the generators are designed to regulate for constant current and thus give a voltage varying with the load, and are connected in series with constant current generators series con- nection is stable, parallel connection unstable and feed constant current, at variable voltage, into the quarter-wave line. The initial value of the resultant m. Single-phase short-circuit current of a three-phase turbo-alternator.
The disruptive strength of materials, and its effect on the electrostatic field of the circuit. Types of waves: standing waves, traveling waves, alter- nating-current waves. Time decrement of oscillation, and energy transfer be- tween sections of complex oscillating circuit. This then gives the additional equation Kol. Some examples may illustrate the phenomena discussed in the preceding paragraphs.
If, however, at the moment of change, the transient term of the preceding change has not yet vanished, then the starting or terminal values of the electric quantities, as i and e , also contain a transient term, namely, that existing at the end of the preced- ing period. In the rotating field, or the polyphase m. The final chapter deals with the operational characteristics of an electrical power system. Power dissipated in the resistance and the conductance of a circuit section. It is interesting to note that here the general equations of alternating-current long-distance transmission appear as a special case of the equations of the traveling wave, and indeed can be considered as a section of a traveling wave, in which the accelera- tion constant s equals the exponential decrement u. These phenomena are essentially independent of the fre- quency and the wave shape of the impressed e. Such an important topic requires a careful approach, and Charles A.
The time, t, then is the independent variable, trie quantities as current, e. This book provides information pertinent to the analysis of transient phenomena in electro-mechanical systems. With voltages per gap varying from 2280 to 2560, 300 gaps would, by addition, give a total voltage of about 730,000, while the actual voltage is only about one-twenty-fourth thereof; that is, the sum of the voltages of many spark-gaps in series may be many times the resultant voltage, and a lightning flash may pass possibly for miles through clouds with a total potential of only a few hundred million volts. Since 81 is the difference of two exponential functions of different decrement, it follows that as function of the time t, I rises from to a maximum and then decreases again to zero, as shown in Fig. Wave length, attenuation, depth of penetration. Numerous example problems illustrate and reinforce the concepts discussed. Equations of the equivalent sine waves of the mercury arc rectifier.
Elimination of the complex exponent in the group equa- tions. The differential equations of the transformer coil, and their integral equations. Especially is this the case with two classes of phenomena closely related to each other: the phenomena of distributed capacity and those of high frequency currents. Ferguson, of Union University, who has carefully revised the manuscript, the equations and the numerical examples and checked the proofs, so that it is hoped that the errors in the work are reduced to a minimum. This text then explains the electromagnetic and electro-mechanical phenomena, taking into account the mutual action between the components of the system. Assuming the condenser to be designed for 10,000 volts alternating impressed e.
In Chapter 8, applications to various problems in semiconductor physics are dealt with. As result, a very great distortion of the field occurs, and the magnetic flux is concentrated at the pole corner. At very high frequencies, when dealing with alternating magnetic circuits, the outer surface and not the section is, there- fore, the dominating feature. C x represents the capacity against ground, C 2 represents the capacity between adjacent turns, and C s the capacity between adjacent layers of the coil. At five billion cycles per second, the wave length is about 6 cm. Final equations of quarter- wave and half-wave oscilla- tion. The third section gives the theory of phenomena which are alternating in time and transient in distance, and the fourth and last section gives phenomena transient in time and in distance.
The internal constants r t and x x are equal, and in the most important range of high frequencies, from 10,000 to 1,000,000 cycles, the external constants r, and x 2 are not very different from each other and their plotted curves intersect at some certain frequency. Mviual inductance of two conductors of finite length at con- siderable distance from each other. Effect of inductance, as loading, and leakage, on attenu- ation. As an example is shown, in Fig. Transient term of polyphase magnetomotive force.
Case of constant impressed e. Ill until the current of the next half wave 2 has started, i. A few of these transient phenomena were observed and experi- mentally investigated in the early clays of electrical engineering for instance, the building up of the voltage of direct-current generators from the remanent magnetism. Numerical example, and its discussion. Conditions and types of free oscillations. Effect of frequency on transient terms to be expected in transformers. This gives the following constants: Current Impressed e.
In this case the space angles 7t + t x and n — r 2 and the time angles tz + X and n - 2 are identical. It is possible, however, to derive from the constants of the circuit, r, L, g, C, and without any assumption whatever regard- ing current, voltage, etc. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant. Construction of numerical examples, by table. Theory and calculation of transient electric phenomena and oscillations. Starting current of an inductive circuit. Quarter-wave circuits thus may be used, and are used, to pro- duce extremely high voltages, and if a sufficiently high frequency is used — 100,000 cycles and more, as in wireless telegraphy, etc.