W. L. Waters MODERN DEVELOPMENT IN SINGLE-PHASE GENERATORS Vol. xxvii-1908, pp. 1069-1076 Brief general discussion of difficulties in the design of large singlephase turbo-generators, due to pulsation of armature reaction and to mechanical stresses on end connections when carrying short-circuit current. Discussion, incorporated with paper by Jens Bache-Wiig on "Application of Fractional Pitch Windings to Alternating-Current Generators." APPLICATION OF FRACTIONAL PITCH WINDINGS TO ALTERNATING-CURRENT Jens Bache-Wiig GENERATORS Vol. xxvii-1908, pp. 1077-1085 Brief general outline of the advantages of the fractional pitch winding with respect to utilization of copper and space and to facilitation of manufacture, followed by a short discussion of its effect on armature reaction and wave form. Discussion (including paper by B. A. Behrend on "A New Large Generator for Niagara Falls," and paper by W. L. Waters on "Modern Development in Single-Phase Generators"), pp. 1086-1097, by Messrs. Wm. J. Foster, B. A. Behrend, L. Schuler, F. H. Clough, Chas. P. Steinmetz and W. L. Waters. General remarks on the design of single-phase turbo-alternators and comments on the mechanical design of 10,000-h.p. high-speed generators. THE RELATIVE PROPORTIONS OF COPPER AND IRON IN ALTERNATORS Carl J. Fechheimer Vol. xxvii-1908, pp. 1429-1458 Analytical study of the costs and weights of materials in alternators, expressing the various factors in the form of equations and solving for minimum cost. Example comparing calculations from equations with calculations from actual dimensions. Discussion, pp. 1457-1458, by Messrs. W. L. Waters and Comfort A. Adams. E. F. W. Alexanderson ALTERNATOR FOR 100,000 CYCLES Vol. xxviii-1909, pp. 399-415 Description of the mechanical design and electrical characteristics of a high-frequency alternator. Discussion, pp. 413-415, by Messrs. John B. Taylor, J. C. Lincoln, David B. Rushmore, C. J. Fechheimer, and A. E. Kennelly. Further description of the mechanical and electrical operative characteristics of the 100,000-cycle generator. COMPARATIVE COSTS OF 25-CYCLE AND 60-CYCLE ALTERNATORS Carl J. Fechheimer Theoretical analysis of the cost of material and construction of 25 and 60-cycle alternators of ratings up to 6,500 kw. Discussion, pp. 990-991, by Messrs. J. C. Lincoln, M. G. Lloyd and Carl J. Fechheimer. Relation between armature copper and field copper and rating of alternators. ELECTROMOTIVE FORCE WAVE SHAPE IN ALTERNATORS Comfort A. Adams Vol. xxviii-1909, pp. 1053-1076 Description of a method of calculating wave shape of e. m. f. from flux distribution curve, with tables of correction factors for various types of windings. Examples indicating the relation of winding type to wave shape. Discussion, p. 1077, by Messrs. J. C. Lincoln and Comfort A. Adams. Choice of pitch to eliminate higher harmonics. PARALLEL OPERATION OF THREE-PHASE GENERATORS, WITH THEIR NEUTRALS George I. Rhodes INTERCONNECTED Vol. xxix-1910, pp. 765-790 Analytical development of the relations between the factors that produce neutral currents in star-connected generators with interconnected neutrals, so as to permit a close predetermination of the magnitude of the currents, followed by an application of the equation to existing generators, the results being checked by tests. Remedies for the prevention of these currents are suggested. Discussion, pp. 791-807, by Messrs. H. J. Ryan, S. J. Lisberger, G. I. Rhodes, C. L. Cory, L. B. Stillwell, C. F. Adams, Paul Downing, E. F. Scattergood, W. F. Lamme, P. M. Lincoln, C. A. Adams, S. B. Charters, Jr., W. A. Hillebrand, Ralph D. Mershon, and H. Y. Hall. Some experience with plants operating with star-connected generators with interconnected neutrals. Laboratory reproduction of these conditions. Feasibility of applying author's remedies. C. INDUCTION MACHINES THE INDUCTION MOTOR AND THE ROTARY CONVERTER AND THEIR RELATION TO THE TRANSMISSION SYSTEM Chas. F. Scott Vol. xviii-1901, pp. 371-382 Detailed comparison of induction and synchronous motors as to construction, performance characteristics and operation. General discussion of synchronous converters, induction motor-generators and synchronous motor-generators, bringing out their relation to the generator. Discussion, incorporated with that of paper by E. W. Rice, Jr., on “The Control of High-Voltage Systems of Large Power." NOTES ON MODERN ELECTRIC RAILWAY PRACTICE Albert H. Armstrong current series and induction motors for interurban and trunk line operation. Discussion, incorporated with that of paper by Ernst J. Berg on "Electric Railway Apparatus." ELECTRIC RAILWAY APPARATUS Ernst J. Berg Vol. xviii-1901, pp. 603-630 Discussion of the characteristics and limitations of generators, converters, motor-generators and motors for different kinds of electric railway service. Extended consideration of the relative merits of directcurrent series, and polyphase induction motors in a given numerical instance, comparing performance, efficiency and cost. Discussion (including that of paper by Albert H. Armstrong on "Notes on Modern Electric Railway Practice"), pp. 631-666, by Messrs. Paul Janet, Chas. P. Steinmetz, G. Gillon, Chas. Janisch, Bion J. Arnold, C. O. Mailloux, E. P. Roberts, L. B. Stillwell, A. H. Pott, C. F. Scott, P. K. Stern, H. C. Spaulding, F. S. Holmes, Ernst J. Berg, A. H. Armstrong, and N. C. Sawers. General remarks on the stability of the induction motor for traction purposes. A NOVEL COMBINATION OF POLYPHASE MOTORS FOR TRACTION PURPOSES Ernst Danielson Vol. xix-1902, pp. 527-539 Description of a system of concatenating two motors of unequal numbers of poles so as to get four running speeds. Comparison of acceleration characteristics, torque, energy, efficiency, etc., with directcurrent series, plain, induction and concatenated induction motors. Abstracted by Dr. Chas. P. Steinmetz on page 495. Discussion (including that of paper by Carl L. DeMuralt on "Some Notes on European Practice in Electric Traction with Three-Phase Alternating Current"), pp. 540-555, by Messrs. C. P. Steinmetz, C. O. Mailloux, Henry G. Stott, W. N. Smith, W. J. Hammer, Townsend Wolcott, Frederick V. Henshaw, and C. L. DeMuralt. William S. Franklin THE SINGLE-PHASE INDUCTION MOTOR Vol. xxiii-1904, pp. 429-441 Physical analysis of the performance of the single-phase induction motor, with equations for the principal electrical factors. Application of the Heyland diagram to the single-phase motor. Discussion, pp. 466-469, by Messrs. W. S. Franklin and A. S. McAllister. Criticisms of Steinmetz's method of dealing with the single-phase induction motor. Test showing effect on exciting current of disconnecting one phase of the two-phase motor. Comfort A. Adams THE DESIGN OF INDUCTION MOTORS Vol. xxiv-1905, pp. 649-684 Exposition of a method of calculating the leakage factors of an induction motor and expressing the power-factor in terms of design constants and the exciting current in terms of the torque current. Numerical examples of the application of these methods to actual motors. Discussion, pp. 685-687, by Messrs. W. L. Waters, Charles P. Steinmetz and Comfort A. Adams. Actual degree of accuracy in induction motor construction. Degree of accuracy necessary in design. A. B. Field EDDY CURRENTS IN LARGE SLOT-WOUND CONDUCTORS Vol. xxiv-1905, pp. 761-788 Theoretical investigation of the IR losses caused by eddy currents in conductors imbedded in slots. Loss constants given for various arrangements with different shaped slots with solid and laminated conductors. No discussion. ALTERNATE-CURRENT MACHINERY-INDUCTION ALTERNATORS William Stanley Assisted by G. Faccioli Vol. xxiv-1905, pp. 851-872 Description of induction generators excited with alternating current of frequency differing from that of mechanical rotation. Mode of operation giving theory of e. m. f. regulation, followed by regulation curves from actual tests. Determination of size of exciter and description of type of exciter suitable for obtaining proper e. m. f. characteristics at very low frequencies. Discussion, pp. 873-877, by Messrs. Charles P. Steinmetz, Comfort A. Adams and W. E. Goldsborough. Explanation of the mode of operation by considering the machine a frequency converter. AIR-GAP FLUX IN INDUCTION MOTORS A. S. Langsdorf Vol. xxiv-1905, pp. 919-931 Theoretical and mathematical study of the effect upon flux distribution of varying the number of stator teeth, the exciting current assumed to be a sine wave. Discussion, pp. 932-933, by Messrs. B. A. Behrend, Fitzhugh Townsend, A. H. Pikler, and A. S. Langsdorf. Criticisms of the assumptions made by the author. COMPARISON OF TWO AND THREE-PHASE MOTORS 295-306 Bradley McCormick Vol. XXV-1906, pp. Comparison of design constants of two induction machines of the same rating and built on equal frames-one two-phase and the other threephase. Discussion, pp. 307-309, by Messrs. A. S. McAllister, Bradley McCormick, C. P. Steinmetz, and R. E. Hellmund. Calculation of exciting current from volume of core and air-gap. FRACTIONAL PITCH WINDINGS FOR INDUCTION MOTORS C. A. Adams, W. K. Cabot and G. AE. Irving, Jr., Vol. xxvi-1907, pp. 1485-1503 Derivation of formulas for various leakage reactances-slot, tooth tip, coil end and belt, followed by actual tests, the results of which are plotted as curves. Discussion, incorporated with paper by R. E. Hellmund on "Zigzag Leakage of Induction Motors." R. E. Hellmund ZIGZAG LEAKAGE OF INDUCTION MOTORS Vol. xxvi-1907, pp. 1505-1524 Definitions and derivations of formulas for magnetic leakage coefficients of induction motors, leading up to the formula for light-load zigzag leakage coefficient. General discussion of the subject. Effect of fractional pitch winding on excitation of induction motors. Discussion (including that of paper by C. A. Adams, W. K. Cabot and G. AE. Irving, Jr., on "Fractional Pitch Windings for Induction Motors"), pp. 1525-1526, by Messrs. J. C. Lincoln, Charles P. Steinmetz, B. T. McCormick, Comfort A. Adams, and A. S. McAllister. THE NON-SYNCHRONOUS GENERATOR IN CENTRAL STATION AND OTHER WORK W. L. Waters Vol. xxvii-1908, pp. 157-180 General characteristics of induction generator; method of operation; methods of excitation; regulation; behavior on short-circuits; advantages in connection with steam turbine and gas engine drive. Analytical discussion of its suitability to different kinds of servicelarge and small central stations and in the production of direct current with steam turbines. Discussion, incorporated in paper by J. E. Woodbridge on "Some Features of Railway Converter Design and Operation." CALCULATION OF THE STARTING TORQUE OF SINGLE-PHASE INDUCTION MOTORS WITH PHASE-SPLITTING STARTING DEVICES I. E. Hanssen Vol. xxvii-1908, pp. 373-375 INDUCTION MOTORS FOR MULTI-SPEED SERVICE, WITH PARTICULAR H. C. Specht Vol. xxvii-1908, pp. 1177-1195 Analytical and experimental investigation of performance and characteristics of a Cascade set arranged for direct and differential concatenation. |
